Higher survival rate in total knee arthroplasty after high tibial osteotomy than that after unicompartmental knee arthroplasty.

PURPOSE: The objective of this study was to evaluate the survival rates and complications in TKA after UKA and HTO as compared with primary TKA using national health data. It was hypothesized that survival and complication rates would be worse in patients with a history of UKA or HTO compared to primary TKA. METHODS: Based on a list of patients who underwent TKA from Korean National Health Insurance database, 315,071 underwent primary TKA (group A); 2177 TKA after HTO (group B); and 1284 TKA after UKA (group C). Revision rates were compared between the groups using log-rank tests and adjusted hazard ratios (HR) of groups B and C were compared with those of the reference group (group A). A total of 1000 TKA matched patients were assigned to groups B and C according to propensity score for comparing revision rates after TKA and perioperative complication rates between TKA after HTO and UKA. RESULTS: The overall revision rate was 2.1% in group A, 2.0% in group B, and 4.2% in group C. The revision rate until 10 years after TKA was significantly higher in group B (p = 0.03) or C (p < 0.0001) than in group A. The hazard ratios for revision was significantly higher in group A than in groups B and C at 10 years after index TKA (1.4 in group B and 3.7 in group C). The result of the comparison using PSM between TKA after HTO and UKA showed that TKA after HTO had lower risk of revision than TKA after UKA (HR: 0.41 at 10 years). However, no statistically significant differences in the perioperative complication rate between the two groups were found. (NS, not significant) CONCLUSIONS: TKA after UKA or HTO showed a significantly higher risk of revision than primary TKA. While TKA after HTO showed lower risk of revision than TKA after UKA, no significant differences in complications between TKA after UKA and HTO were found. Thus, surgeons must be aware of the low survival rate in TKA after UKA or HTO, especially in TKA after UKA. LEVEL OF EVIDENCE: III (Retrospective cohort study).

Chronological Analysis of Primary Cervical Spine Infection: A Single-Center Analysis of 59 Patients over Three Decades (1992-2018).

Primary cervical spine infections progress quickly and cause neurological impairment at an early stage. Despite their clinical significance, few studies have investigated primary cervical spine infections, owing to the rarity of the condition. This study analyzed the characteristics of 59 patients treated for primary cervical spine infections between 1992 and 2018 at our hospital. Clinical and radiological analyses were conducted. Moreover, a comparative analysis was performed, incorporating each patient's underlying disease, mortality and complications, and treatment results. Comparison between groups based on the chronological period (1992-2000, 2001-2009, and 2010-2018) revealed that the mean age of onset has increased significantly in recent years. The rate of neurological impairment, duration of antibiotic use, and frequency of underlying disease increased significantly with time. No significant differences among groups were observed in the hematological and microbiological analyses. The incidence rate of epidural abscess and multisegmental infection increased significantly in recent years. There was no statistically significant difference in the complication and mortality rates, according to the time period. We think that prompt diagnosis and appropriate treatment are necessary, considering the current trends in primary cervical spine infection.

A comparative study of 21,194 UKAs and 49,270 HTOs for the risk of unanticipated events in mid-age patients from the national claims data in South Korea.

BACKGROUND: Both high tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA) are well-established treatments for medial knee osteoarthritis (OA). However, over the past 20 years, results of comparisons of long-term survival rates and outcomes have remained controversial. Furthermore, in patients at the boundary age, from 50 to 70 years, considering age as a treatment indication, selecting a surgical method is difficult. Therefore, we aimed to investigate conversion rates to total knee arthroplasty (TKA) and perioperative adverse outcomes between the two surgical methods in mid-age patients. METHODS: We extracted data from the Korean National Health Insurance claims database. A total of 70,464 patients aged between 50 and 70 years, considered as mid-age patients were included in the final study population. We used a multivariable Cox proportional hazard regression model, adjusting for potential confounders such as age, sex, insurance type, region of residence, hospital type, comorbidities, and the Charlson comorbidity Index (CCI). RESULTS: Of the 70,464 patients, 21,194 were treated with UKA and 49,270 were treated with HTO. HTO showed a higher risk of revision than UKA at five, and 10 years and during the whole observation period. The incidence of deep vein thromboembolism, and surgical site infection was significantly higher in UKA than in HTO. CONCLUSIONS: It is important to choose an appropriate surgical method considering that UKA has better results in terms of long-term survival rates but may have a higher incidence of various complications.

Older age increases the risk of revision and perioperative complications after high tibial osteotomy for unicompartmental knee osteoarthritis.

Among various patient risk factors affecting survival after high tibial osteotomy (HTO), the ideal age limit for HTO is unclear. This study was performed to evaluate the effect of age on survival rate and complications after HTO for medial unicompartmental osteoarthritis. Among of 61,145 HTO patients from Korean National Health Insurance database, 41,112 patients underwent the procedure before the age of 60 years (Group A), 13,895 patients between the age of 60 and 65 years (Group B), and 6138 patients after the age of 65 years (Group C). We compared the survival rate in person-years among the three groups from the date of primary surgery until subsequent total knee arthroplasty. Perioperative complications were also recorded. The adjusted hazard ratio (HR) were calculated using the multivariable Cox proportional hazard regression model, adjusting for the potential confounders: age, sex, type of medical insurance, region of residence, hospital type, comorbidities, and Charlson comorbidity index score. The total number of HTO increased 6.5-fold, especially in patients aged > 65 years (by 8.2-fold) from 2008 to 2018. The overall revision rate was 4.2% in Group A, 6.4% in Group B, and 7.3% in Group C. The 5- and 10-year revision rate was significantly lower in Group A (p < 0.001), but no difference between Groups B and C. After adjusting for potential confounders, multivariable regression analysis revealed that revision rate was significantly lower in Group A than Group B (HR: 0.57; p < 0.0001), but no difference between Groups B and C. The incidence of complications was also significantly lower in Group A than in other groups. The inferior survival rate and more perioperative complications after HTO was found in old patients (aged ≥ 60 years) than in young patients. Therefore, the patient age is one of the predicting factors for a high risk of failure after HTO.

Surgical Outcomes for C2 Tear Drop Fractures: Clinical Relevance to Hangman's Fracture and C2-3 Discoligamentous Injury.

OBJECTIVE: To analyze characteristics of surgically managed tear drop (TD) fractures of the C2 axis associated with other injuries such as hangman's fracture and C2-3 discoligamentous injury as well as treatment outcomes. METHODS: A total of 14 patients (eight men and six women) with TD fractures of the C2 , who were surgically treated at four national trauma centers of tertiary university hospitals from January 2000 to December 2017, were included in this retrospective study. The mean age of the patients was 45.5 years (ranging from 19 to 74 years). The characteristics, surgical treatment methods (anterior fusion vs posterior fusion), and results of 14 TD fractures of the C2 were analyzed retrospectively. And the clinical relevance between C2 TD fracture and hangman's fracture and C2-3 discoligamentous injury was investigated through the co-occurrence between injuries. The mean follow-up time after surgery was 22.6 months (ranging from 12 to 60 months). RESULTS: Among 14 patients with TD fracture of the C2 , four patients (28.6%) had anterior TD fracture and 10 patients (71.4%) had posterior TD fracture. All 10 posterior TD fracture patients had anterior C2-3 displacement. While two of four anterior TD fracture patients had posterior C2-3 displacement, the remaining two did not. All 14 patients of TD fracture had at least two or more other associated C2 injuries as well as C2-3 discoligamentous injuries. About 92.9% (13/14) of the patients had typical or atypical hangman's fracture; 100% (10/10) of the posterior TD fracture patients had hangman's fracture, but 75% (3/4) of the anterior TD fracture had hangman's fracture. At admission, 13 patients were neurologically intact. However, the remaining patient had spinal cord injury with American Spinal Injury Association (ASIA) impairment scale B with C2-3 bilateral facet dislocation. All four anterior TD fracture patients underwent posterior C2-3 fusion. While four of 10 posterior TD fracture patients underwent C2-3 anterior fusion, the remaining six underwent posterior fusion. At last follow-up, 100% (14/14) of the patients achieved solid fusion, and visual analog scale for neck pain was significantly improved (5.9 vs 2.2, P < 0.001). One patient with ASIA impairment scale B had significantly improved to scale D. No major complications occurred. CONCLUSION: Our study showed that surgically managed TD fractures of the C2 showed a high incidence of other associated spine injuries including hangman's fracture and C2-3 discoligamentous injury. Therefore, special attention and careful radiologic evaluation are needed to investigate the presence of other associated spine injuries including hangman's fracture and C2-3 discoligamentous injury, which are likely to require surgery.

How Should Patients with a Thoracolumbar Injury Classification and Severity Score of 4 Be Treated?

The thoracolumbar injury classification and severity score (TLICS) system help surgeons decide whether patients should undergo initial operative treatment or nonoperative treatment. However, the best treatment for patients with TLICS 4 fracture remains unknown. The aim of this study was to identify the risk factors for nonoperative treatment failure in patients with TLICS 4 fracture and establish treatment standards for TLICS 4 fractures. This study included 44 patients with TLICS 4 fracture who initially received nonoperative treatment. We divided these patients into two groups: the successful nonoperative treatment group included 18 patients, and the operative treatment group after nonoperative treatment failure included 26 patients. In multiple logistic regression analysis, spinal canal compromise (odd ratio = 1.316) and kyphotic angle (odd ratio = 1.416) were associated with nonoperative treatment failure in patients with TLICS 4 fracture. Other factors, including age, sex, BMI, initial VAS score, and loss of vertebral body height, were not significantly associated with nonoperative treatment failure in these patients. Spinal canal compromise and kyphotic angle were associated with nonoperative treatment failure in patients with TLICS 4 fracture. Therefore, we recommend the surgeon observe spinal canal compromise and kyphotic angle more carefully when deciding on the treatment of patients with TLICS 4 fracture.

Clinical Outcomes of Anterolateral Ligament Reconstruction or Lateral Extra-articular Tenodesis Combined With Primary ACL Reconstruction: A Systematic Review With Meta-analysis.

BACKGROUND: Residual rotational instability after isolated anterior cruciate ligament reconstruction (ACLR) has been a challenge for many years. Anterolateral extra-articular procedures (AEAPs), including anterolateral ligament reconstruction (ALLR) or lateral extra-articular tenodesis (LET), are performed as a surgical option for additional rotational stability, but clear evidence for their usefulness is lacking. PURPOSE: To conduct a systematic review and meta-analysis of the literature regarding the efficacy of AEAP in primary ACLR. STUDY DESIGN: Systematic review; Level of evidence, 3. METHODS: A literature search, data extraction, and quality assessment were conducted by 2 independent reviewers. MEDLINE, EMBASE, and the Cochrane Library were searched in April 2020, following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A total of 3444 studies were screened, and 20 studies (11 randomized controlled trials and 9 nonrandomized studies) were evaluated. Functional outcomes, stability, and complications were compared between patients who underwent primary ACLR with AEAP and those who underwent isolated primary ACLR. For subgroup analysis, outcomes were compared according to AEAP technique (ALLR vs LET) and time from injury to surgery (≤12 vs >12 months). The methodological quality of the included studies was assessed using the Cochrane risk-of-bias tool, Jadad scale, and Newcastle-Ottawa Scale. RESULTS: Compared with isolated ACLR, combined ACLR with AEAP led to improved pivot-shift grades and graft failure rates, regardless of the AEAP technique or of time from injury to surgery. A limited, marginal improvement in subjective function score was observed in patients who underwent AEAP combined with ACLR. In contrast to ALLR, patients who underwent LET combined with ACLR had an increased risk of knee stiffness and adverse events. CONCLUSION: Our review suggests that when there is a need to improve rotational stability and subjective function, AEAP combined with primary ACLR can be considered regardless of time from injury. ALLR appeared to be a better option for improving rotational stability compared with LET.

Proposal of Treatment Strategy for Pedicle Fractures of the C2: An Analysis of 49 Cases.

Spine surgeons often confuse C2 pedicle fractures (PFs) with pars interarticularis fractures. In addition, little information is available about the characteristics and treatment strategies for C2 PFs. We sought to investigate the characteristics of C2 PFs and to propose an appropriate treatment strategy. A total of forty-nine patients with C2 PFs were included in this study. We divided these patients into unilateral and bilateral C2 PF groups. The incidence rates and characteristics of other associated C2 and C2-3 injuries, and other cervical injuries, were evaluated. In addition, treatment methods and outcomes were analyzed. Twenty-two patients had unilateral C2 PFs and twenty-seven patients had bilateral C2 PFs. Among the cases of unilateral C2 PFs, all patients had one or more other C2 fractures, and twenty patients (90.9%) had one or two C2 body fractures. Meanwhile, among the cases of bilateral C2 PF, all patients had two or more other C2 fractures and one or two C2 body fractures. In unilateral C2 PFs, three patients with C2-3 anterior slip or adjacent cervical spine (C1-3) injury underwent surgery and nineteen patients (86.4%) were treated with conservative methods. In bilateral C2 PFs, three patients with C2-3 anterior slip or SCI at C2-3 underwent surgery and twenty-four patients (88.9%) were treated with conservative methods. Our results showed that C2 PFs do not occur alone and are always accompanied by other associated C2 injuries. C2 PFs should, generally, be thought of as a more complex fracture type than hangman's fracture or dens fracture. Despite the complex fracture characteristics, most C2 PFs can be managed with conservative treatment. However, surgical treatments should be considered if the C2 PFs are accompanied by the C2-3 anterior slip and adjacent cervical spine injury.

Does meniscectomy have any advantage over conservative treatment in middle-aged patients with degenerative medial meniscus posterior root tear?

BACKGROUND: The best treatment for degenerative medial meniscus posterior root tear (MMPRT) remains controversial. This study aimed to compare the clinical and radiological outcomes of arthroscopic meniscectomy and conservative treatment for degenerative MMPRT. METHODS: From January 2007 to December 2014, 146 patients (Meniscectomy group, 90; Conservative group, 56) were evaluated. Clinical outcomes were assessed using the Visual Analog Scale, International Knee Documentation Committee subjective scoring scale, Tegner activity scale, and Lysholm knee scoring scale at the final follow-up. Radiologic outcomes evaluated the progression of osteoarthritis (OA) according to the Kellgren-Lawrence (K-L) classification. We compared the hip-knee-ankle angle (HKAA), medial proximal tibial angle, tibial posterior slope angle, and width of medial joint space. After an average follow-up of 6.3 years, the survivorship was analyzed using the Kaplan-Meier method. RESULTS: All clinical outcomes were significantly improved in both groups after treatment, with no significant differences between the two groups at the final follow-up. The progression of OA according to the K-L classification, HKAA and width of medial joint space was significantly advanced in the meniscectomy group (p = 0.03, 0.04, 0.03, respectively). The 10-year survival rates in the meniscectomy and conservative groups were 87 and 88%, respectively. CONCLUSIONS: This study demonstrated that both conservative treatment and meniscectomy provided symptomatic relief. However, it was confirmed that OA progression was more severe in the meniscectomy. We conclude that arthroscopic meniscectomy had no advantage over conservative treatment in terms of clinical outcomes and OA progression in middle-aged patients with MMPRT. LEVEL OF EVIDENCE: Level III; retrospective comparative study.

The Relationship between Adjacent Segment Pathology and Facet Joint Violation by Pedicle Screw after Posterior Lumbar Instrumentation Surgery.

Transpedicular screw instrumentation systems have been increasingly utilized during the fusion of lumbar spine procedures. The superior segment facet joint violation of the pedicle screw is thought to have potential for accelerating symptomatic adjacent-segment pathology (ASP). The purpose of this study was to investigate the relationship between the superior segment facet joint violation by transpedicular screws and the development of ASP. Among all patients who underwent operations involving one- or two-level posterior lumbar arthrodesis at the Chonnam National University Hospital from 1992 to 2012, 87 patients were selected for this study. Fifty-six patients were included in the ASP group, and 31 were included in the non-ASP group. We used lumbar three-dimensional computed tomography (CT) to assess the violation of the superior facet joint by a transpedicular screw. The assessment is presented in scores ranging from zero to two, with zero indicating no violation (type I); one point indicating suspected violation (type II); and two points indicating definitely facet joint violation (type III). Facet violation was reported in 31 patients in the ASP group (n = 56), and in 13 patients in the non-ASP group (n = 31). The types of facet joint violation according to our scoring system were as follows: type I, 59 screws (52.7%); type II, 26 screws (23.2%); and type III, 27 screws (24.1%) in the ASP group; and type I, 43 screws (69.4%), type II, 14 screws (22.6 %); and type III, 5 screws (8.0%) in the non-ASP group. The score of facet joint violation in each patient according to our scoring system were as follows: 0 points, 25 patients (44.6%); 1 point, 8 patients (14.3%); 2 points, 4 patients (7.1%); 3 points, 11 patients (19.7%); 4 points, 8 patients (14.3%) in the ASP group; and 0 points, 18 patients (58.1%); 1 point, 4 patients (12.9%); 2 points, 7 patients (22.6%); 3 points, 2 patients (6.4%); 4 points, 0 patients (0%) in the non-ASP group. The mean scores were 1.4 points in the ASP group and 0.8 points in the non-ASP group (p < 0.05). We conclude that the position of the pedicle screw farther away from the facet joint surface can reduce the degeneration of the superior adjacent segment. Therefore, close attention to the screw position during surgery may reduce the rate of superior adjacent-segment pathologies.

Analysis of Nonunion in Conservatively Managed Anterior Tear Drop Fractures of C2 Vertebra.

Many anterior C2 (2nd cervical vertebra) tear drop (TD) fractures can be successfully managed with conservative treatment. However, due to the occurrence of nonunion, large-sized or complex anterior C2 TD fractures undergo surgical treatment. To date, no surgical treatment guidelines are available about anterior C2 TD fractures. Therefore, we performed this study to investigate the factors that may affect nonunion for anterior C2 TD fractures and to suggest surgical treatment guidelines. Thirty-three patients with anterior C2 TD fractures, who underwent conservative treatment and had a minimum 1-year follow-up, were divided into union (N = 26) and nonunion (N = 7) groups. Their radiological and clinical data were analyzed retrospectively and compared between the two groups. The avulsion fracture ratio (29.5% vs. 43.3%, p < 0.05) and fracture displacement (3.6 mm vs. 5.1 mm, p < 0.05) were higher in the nonunion group compared to the union group. Incidence of associated C2 injury was higher in the nonunion group compared to the union group (15.4% vs. 57.1%, p < 0.05). Union status was negatively correlated with associated C2 injury (correlation coefficient, CC = -0.398, p < 0.05). Our results suggest that surgical treatment could be considered for anterior C2 TD fractures with an avulsion fracture ratio > 43%, fracture displacement > 5 mm, or associated C2 injury.

Proposal of New Radiological Classification and Treatment Strategy for Transverse Fractures of the C2 Axis Body.

OBJECTIVE: To investigate the characteristics of transverse fractures of the C2 axis body diagnosed on sagittal computed tomography (CT) and to propose new classification and appropriate treatment strategies. METHODS: A retrospective study was performed by enrolling 49 patients (26 men and 23 women) with transverse fractures of the C2 axis body who were treated at four national trauma centers of tertiary university hospitals from January 2000 to December 2017. The mean age of the patients was 60.8 years (ranging from 21 to 90 years). We classified 49 transverse fractures of the C2 body into three types based on fracture trajectories involving superior articular facet (SAF) and lateral cortex (LC) of the C2 body on coronal CT as follows: Type 1, involvement of C2 SAF on both sides; Type 2, unilateral involvement of C2 SAF on one side and LC on the other side; Type 3, involvement of LC on both sides. The characteristics, treatment methods, and results of 49 transverse fractures of the C2 body were analyzed. Mean follow-up was 12.6 months (ranging from 12 to 26 months). RESULTS: Twenty-six (53.1%) patients were Type 1, 21 (42.9%) were Type 2, and 2 (4.0%) were Type 3. Correlation coefficients for intra-observer and inter-observer reliabilities of classification were 0.723 and 0.598 (both, P < 0.001), respectively. About 40.8% (7 Type 1 and 13 Type 2) of the patients had fracture displacement >3 mm; Incidence of fracture displacement >3 mm was higher in Type 2 than Type 1 (61.9% vs 26.9%, P < 0.05). About 79.6% (20 Type 1, 17 Type 2 and 2 Type 3) of the patients were treated conservatively, and 20.4% (6 Type 1 and 4 Type 2) underwent surgery. At last follow-up, 47 out of 49 patients achieved fusion; overall fusion rate was 95.9%. All conservatively treated Type 1 and Type 3 patients achieved fusion. Out of 17 conservatively treated Type 2 patients, 15 achieved fusion but two developed nonunion; however, two nonunion patients opted not to undergo surgery. Subgroup analysis showed that Philadelphia brace caused nonunion significantly in fracture displacement >3 mm compared to Minerva brace/Halovest (100% vs 0%, P < 0.05). All surgically treated Type 1 and 2 patients achieved fusion. In terms of clinical outcomes, neck pain visual analog scale and neck disability index were significantly improved (both, P < 0.01). According to Odom's criteria, 93.9% (46/49) of the patients achieved satisfactory outcomes. No major complications occurred. CONCLUSIONS: The majority of transverse fractures of C2 body can be treated conservatively. However, surgery or rigid Minerva brace/Halovest should be considered for Type 2 transverse fractures of the C2 body with fracture displacement >3 mm.

Anterior C2-3 fusion surgery alone for highly displaced Hangman's fracture with severe angulation of C2-3 of more than 30°.

BACKGROUND: Highly displaced Hangman's fracture is a very rare and extremely unstable fracture of the C2 axis. Combined anteroposterior or posterior long-segment fusion surgery is typically performed for the treatment of highly displaced Hangman's fracture. However, these kinds of surgeries increase the risk of complications, loss of motion, and hospital costs. OBJECTIVE: We sought to investigate the surgical outcomes of anterior C2-3 fusion surgery alone for highly displaced Hangman's fractures with severe angulation of C2-3 by more than 30° and discoligamentous injury. METHODS: A total of five patients (four men and one woman) were included in this study with a mean age of 40.4 years (range, 26-70 years). The mean follow-up period after surgery was 37.2 months (range, 12-96 months). The fracture characteristics, treatment methods, and outcomes were retrospectively analyzed. RESULTS: All five patients had type II Hangman's fractures (according to the Levine and Edwards classification scheme). None of the included patients had neurologic deficit or other spine injury but all patients had complete C2-3 discoligamentous injury. Before surgery, all patients successfully achieved closed reduction by skull traction, followed by C2-3 anterior decompression and fusion (ACDF) with plating. For interbody grafting, three patients received a polyetheretherketone (PEEK) cage filled with an autogenous cancellous iliac bone graft and two received autogenous tricortical iliac bone grafts. Severe angulation (39.2° vs. 3.0°, P < 0.001) and severe displacement (76.1% vs. 4.0%, P < 0.001) of C2-3 were both significantly corrected after surgery. All patients had achieved solid fusion at last follow-up. In terms of clinical outcomes, the mean neck pain visual analog scale score was significantly improved (8.6 points vs. 1.8 points, P < 0.001). The mean neck disability index value was also significantly improved (45.4 points vs. 13.0 points, P < 0.01). According to Odom's criteria, all patients achieved satisfactory outcomes. No major complications occurred. One patient complained of dysphagia, but recovered after three months with conservative treatment. CONCLUSIONS: Preoperative closed reduction and anterior C2-3 fusion surgery alone should be considered as a less-invasive and useful surgical option for highly displaced Hangman's fracture with severe angulation of C2-3, which is an extremely unstable fracture of the C2 axis.

Characteristics of Osteoporosis & Osteoporotic Fractures in Korea Based on Health Insurance Review and Assessment (HIRA) Database: 2009-2017.

To investigate the incidence and characteristics of osteoporosis and osteoporotic fractures in Korea, we used the Health Insurance Review and Assessment Service (HIRA) database. Patients over 50 years old, who were diagnosed or treated for osteoporosis and osteoporotic fractures in all hospitals and clinics, were analyzed between 1 January 2009 and 31 December 2017 by using the HIRA database that contains prescription data and diagnostic codes. These data were retrospectively analyzed by decade and age-specific and gender-specific incidents in each year. We also evaluated other characteristics of patients including medication state of osteoporosis, primary used medical institution, regional-specific incidence of osteoporosis, and incidence of site-specific osteoporotic fractures. The number of osteoporosis patients over 50 years old, as diagnosed by a doctor, steadily increased from 2009 to 2017. The number of osteoporosis patients was notably greatest in the 60's and 70's age groups in every study period. Patients undergoing treatment for osteoporosis increased significantly (96%) from 2009 to 2017. Among the patients diagnosed with osteoporosis, the proportion who experienced osteoporotic fracture increased gradually (60%) from 2009 to 2017. The number of patients with osteoporotic fractures of the spine and hip was highest in the 70 to 90 age range, and the number of patients with osteoporotic fractures in the upper and lower extremities was highest in the 50 to 70 age range. Understanding the trends of osteoporosis in Korea will contribute to manage the increased number of patients with osteoporosis and osteoporotic fractures.

Adult Spinal Cord Injury without Major Bone Injury: Effects of Surgical Decompression and Predictors of Neurological Outcomes in American Spinal Injury Association Impairment Scale A, B, or C.

The cervical spine can be injured even in the absence of radiographic abnormality, and the best surgical treatment for adult spinal cord injury without bone injury is debated. The aim of this study was to retrospectively investigate the effect of surgical decompression for severe adult spinal cord injury without major bone injury and to establish predictors of good neurological outcome. We analyzed 11 patients who underwent surgical decompression in severe adult spinal cord injury without major bone injury patients classified as American Spinal Injury Association Impairment Scale (AIS) grade A, B, or C. Neurological assessments were performed using AIS at preoperative and postoperative 1-year follow-up. Radiological evaluations were performed using cervical magnetic resonance imaging (MRI) at preoperative. Seven cases were classified as AIS grade A; two cases as AIS grade B; and two cases as AIS grade C. Five of 11 (45.5%) patients showed improved neurological grade 1-year postoperatively. Intramedullary lesion length (IMLL) (p = 0.047) and compression rate (p = 0.045) had the most powerful effect on AIS grade conversion. This study shows that the fate of the injured spinal cord is determined at the time of the injury, but adequate decompression may have limited contribution to the recovery of neurological function. Compression rate and IMLL on MRI can be used as a predictor of neurological recovery.

Traumatic atlanto-axial rotatory subluxation and dens fracture with subaxial SCIWORA of Brown-Sequard syndrome: A case report.

RATIONALE: A case of traumatic atlanto-axial rotatory subluxation (AARS), dens fracture, rupture of transverse atlantal ligament (TAL), and subaxial spinal cord injury without radiographic abnormality (SCIWORA) of Brown-Sequard syndrome has never been reported in a child. PATIENT CONCERNS: A 7-year-old boy presented to hospital with torticollis, neck pain, and limited neck rotation after a seat-belt injury sustained during a car accident. Neurologic examination revealed right-side motor weakness and left-side sensory abnormality, known as Brown-Sequard syndrome. DIAGNOSIS: Radiologic examinations revealed type II AARS (Fielding and Hawkins classification), increased atlanto-dental interval (ADI) of 4.5 mm due to a type 1B TAL rupture (Dickman classification), a displaced transverse dens fracture along with an ossiculum terminale, and an intramedullary hemorrhage on the right side of the spinal cord at C3-4. INTERVENTIONS: The patient immediately received methylprednisolone, and his motor weakness and sensory abnormality gradually improved. At the same time, the patient underwent initial halter traction for 2 weeks, but he failed to achieve successful reduction and required manual reduction under general anesthesia. OUTCOMES: At the 7-month follow-up visit, radiologic examinations showed a corrected type II AARS that was well maintained and normalization of the ADI to 2 mm. The reduced transverse dens fracture was well maintained but still not united. All clinical symptoms were significantly improved, except the remaining motor weakness of the right upper extremity. LESSONS: To the best of our knowledge, this is the first report of traumatic AARS, dens fracture, TAL rupture, and subaxial SCIWORA of Brown-Sequard syndrome in a child. Appropriate diagnosis and careful treatment strategy are required for successful management of complex cervical injuries in a child.

Traumatic atlantoaxial anteroinferior subluxation with dens and Hangman fractures: A case report.

RATIONALE: Traumatic atlantoaxial anteroinferior subluxation associated with a dens fracture and a Hangman fracture is a very rare and complex injury. Therefore, appropriate surgical strategy is not established. PATIENT CONCERNS: An 85-year-old female presented with posterior neck pain and atypical neck position caused after rolling down a hill. Although neurological examinations for motor, sensory, gait, and reflex tests were normal, the patient complained of an abnormal neck posture. DIAGNOSES: Radiological examinations revealed an atlantoaxial anteroinferior subluxation with kyphosis, a type IIA dens fracture (Anderson and D'Alonzo classification) with an anterolateral rotatory angulation of type IIA dens fracture fragment, and a type I Hangman fracture (Levine and Edwards classification). Nevertheless, the transverse atlantal ligament was intact. INTERVENTIONS: We considered that the intact transverse atlantal ligament and kinking of the type IIA dens fracture fragment into the left lateral mass of C1 prevented a spinal cord injury by blocking a further displacement of C1 to C2. Due to the patient's osteoporosis and the anterolateral rotatory angulated type IIA dens fracture fragment, a forceful reduction of the atlantoaxial anteroinferior subluxation with kyphosis could pose a high risk of fixation failure and spinal cord injury. Therefore, we performed in-situ posterior C1-2 fusion using a C1 lateral mass screw and C2 lamina screw fixations. OUTCOMES: At 1 year after surgery, the bone union of all fractures was achieved in the kyphosis state. Furthermore, the patient's clinical symptoms were improved with no neurological deficit. LESSONS: A thorough radiological examination and appropriate surgical strategy are important for successful diagnosis and treatment of a complex C1-2 injury.

Comparison of Preoperative Bone Density in Patients With and Without Periprosthetic Osteolysis Following Total Ankle Arthroplasty.

BACKGROUND: Modern total ankle arthroplasty (TAA) prostheses are uncemented press-fit designs whose stability is dependent on bone ingrowth. Preoperative insufficient bone density reduces initial local stability at the bone-implant interface, and we hypothesized that this may play a role in periprosthetic osteolysis. We aimed to investigate the preoperative bone density of the distal tibia and talus and compare these in patients with and without osteolysis. METHODS: We enrolled 209 patients (218 ankles) who underwent primary TAA using the HINTEGRA prosthesis. The overall mean follow-up duration was 66 (range, 24-161) months. The patients were allocated into 2 groups according to the presence of periprosthetic osteolysis: the osteolysis group (64 patients, 65 ankles) and nonosteolysis group (145 patients, 153 ankles). Between the 2 groups, we investigated and compared the radiographic outcomes, including the Hounsfield unit (HU) value around the ankle joint and the coronal plane alignment. RESULTS: HU values of the tibia and talus measured at 5 mm from the reference points were higher than those at 10 mm in each group. However, comparing the osteolysis and nonosteolysis groups, we found no significant intergroup difference in HU value at every measured level in the tibia and talus (P > .05). Concerning the coronal plane alignment, there were no significant between-group differences in the tibiotalar and talar tilt angles (P > .05). CONCLUSION: Patients with osteolysis showed similar preoperative bone density of the distal tibia and talus compared with patients without osteolysis. Our results suggest that low bone density around the ankle joint may not be associated with increased development of osteolysis. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Modified Pedicle Subtraction Osteotomy for Osteoporotic Vertebral Compression Fractures.

OBJECTIVE: To evaluate the cases of osteoporotic compression fracture with kyphotic deformity treated with modified pedicle subtraction osteotomy and analyze the usefulness of this osteotomy. METHODS: Twenty patients (nine men, 11 women; mean age, 66.4 years; mean follow-up duration, 39.6 months) who underwent modified pedicle subtraction osteotomy at our hospital between November 2003 and July 2012 with a minimum follow-up period of 2 years were included. All cases were injuries induced by a fall incurred while standing or lifting heavy objects without high-energy trauma. The mean bone mineral density-dual energy x-ray absorptiometry (BMD-DEXA) was 0.673 g/cm2 (0.571-0.740 g/cm2 ), which was -2SD below normal, indicating severe osteoporosis. The indications for surgery included gait disturbance due to severe pain with pseudarthrosis, increased kyphotic angle, and progressive neurological symptoms. We evaluated Japanese Orthopaedic Association scores, Oswestry Disability Index scores, bone union, change in kyphotic angle, estimated blood loss, complications, and the patient's overall clinical satisfaction. RESULTS: The collapsed vertebrae were thoracic (T9, 11, 12 ) in 13 cases and lumbar (L1 ) in seven cases. The mean pre- and post-operative kyphotic angles were 26.2 ± 9.9 degrees and 8.3 ± 8.1 degrees, showing an 18.3-degree correction. Plain radiography at the last follow-up showed a mean angle of 17.9 ± 12.6 degrees, indicating a 9.5-degree correction loss. The overall correction was 8.2 degrees. Bony union was achieved at the last follow-up in all cases. Clinical outcomes showed improvement in mean Japanese Orthopaedic Association score from 13.2 to 21.7 and mean Oswestry Disability Index score from 40.3 to 13.6. Overall clinical patient satisfaction showed 12 excellent results, five moderate results, and three poor results. Mean operation time was 4.2 h (range, 4-6 h). The overall mean estimated blood loss (EBL) was 1098 mL (range, 750-1370 mL). The mean hospital stay was 3.6 weeks (range, 2-6 weeks). There was one case of cauda equina syndrome at 2 days postoperatively, and two cases of screw loosening. There were no cases of distal junctional kyphosis, but there were two cases of proximal junctional kyphosis. CONCLUSIONS: Despite limited correction of kyphotic angle, our modified pedicle subtraction osteotomy technique resulted in satisfactory outcomes in our patients, who had persistent severe back pain, increased kyphotic angle with pseudarthrosis, and progressive neurologic deficits. Nevertheless, this procedure requires careful follow-up and strict surgical indications because of the risk of neurological damage and technical problems.

Percutaneous Pedicle Screw Fixation in Thoracolumbar Fractures: Comparison of Results According to Implant Removal Time.

BACKGROUND: The purpose of this study was to determine whether restoration of range of motion (ROM) could be achieved by implant removal after natural bone healing and consolidation of fractured vertebrae and examine whether early removal of the implant could maximize restoration of ROM. METHODS: This study included 30 cases of thoracolumbar fractures without neurological deficit requiring surgery (nine cases of flexion-distraction injuries and 21 cases of burst fractures). Percutaneous pedicle screw fixation (PPSF) was performed at the fractured vertebrae and one level above and one level below the fracture level. Pedicle screws were removed at an average of 12 months after surgery upon healing of fractured vertebrae. The following radiological and clinical findings were evaluated: restoration of anterior vertebral height ratio (AVHR), Cobb angle (CA), ROM, and complications. Sixteen patients who were checked for ROM were divided into two groups based on the time of implant removal: nine patients within 12 months and seven patients after 12 months. Restoration of vertebral height loss and ROM were compared between the two groups. RESULTS: At the final follow-up, significant pain relief and restoration of AVHR and CA were achieved in patients who underwent PPSF. Patients who had implant removed within 12 months after surgery had better ROM recovery than those who had implant removed after 12 months postoperatively. There were no significant differences in AVHR and CA between the two groups. CONCLUSIONS: PPSF followed by implant removal after healing of fractured body appears to be effective in achieving restoration of ROM. In our study, early removal of implant within 12 months after surgery was associated with better achievement of ROM than removal after 12 months. In addition, there were no significant differences in restoration of vertebral height between the two groups.