Relationship between the medial cuneiform bone morphology and the severity of hallux valgus.

BACKGROUND: It has been reported on the relationship between the medial cuneiform bone morphology, especially in terms of obliquity, and the severity of hallux valgus (HV), however, no consensus has been obtained. On the other hand, there are no reports on the relationship between the difference in height between the medial and intermediate cuneiforms and the severity of hallux valgus. The purpose of this study was to clarify the relationship between the medial cuneiform bone morphology and the severity of HV. METHODS: The authors retrospectively analyzed 200 feet of 116 patients who had a weightbearing anteroposterior foot radiograph taken between April 2017 and July 2022 and diagnosed with HV. Measurements included the hallux valgus angle (HVA), the intermetatarsal angle (IMA), the distal medial cuneiform angle (DMCA) and the cuneiform first-second length (C1-2D). HV groups were classified into one of three groups: mild (15 ≦ HVA<30°, 9 < IMA<13°), moderate (30 ≦ HVA<40°, 13 ≦ IMA≦20°) and severe groups (HVA≧40°, IMA>20°), and the relationship to DMCA or the difference in height between the medial and intermediate cuneiforms was analyzed. RESULTS: A total of 163 feet of 93 patients were included in this study. There were significant correlations between the HVA and the DMCA (r = 0.47, p <0.001) or the C1-2D (r = 0.64, p <0.001). There was no significant difference in DMCA between the mild and moderate groups (p = 0.14). On the other hand, significant differences in C1-2D were observed between the three groups (mild-moderate; p <0.001, moderate-severe; p = 0.03, mild-severe; p <0.001). IMA was also positively correlated with the DMCA (r = 0.30, p <0.001) or the C1-2D (r = 0.47, p <0.001). However, the DMCA (p = 0.07) and the C1-2D (p = 0.39) did not differ significantly from IMA between the moderate and severe groups. CONCLUSIONS: The difference in height between the medial and intermediate cuneiforms, referred to as C1-2D, is closely associated with the HVA. The C1-2D may influence the progression of HV and be a novel radiographic parameter that indicates severity of HV.

Patient-specific guide systems decrease the major perforation rate of pedicle screw placement in comparison to the freehand technique for adolescent idiopathic scoliosis.

PURPOSE: This study aimed to compare the accuracy of pedicle screw (PS) placement between a low-profile three-dimensional (3D) printed patient-specific guide system and freehand technique for adolescent idiopathic scoliosis (AIS) surgery. METHODS: Patients with AIS who underwent surgery between 2018 and 2023 at our hospital were included in the study. The 3D-printed patient-specific guide was used since 2021 (guide group). PS perforation was classified using Rao and Neo's classification (grade 0, no violation; grade 1, < 2 mm; grade 2, 2-4 mm; grade 3, > 4 mm). Major perforations were defined as grades 2 or 3. The major perforation rate of PS, operative time, estimated blood loss (EBL), and correction rate were compared between the two groups. RESULTS: A total of 576 PSs were inserted in 32 patients (20 patients in the freehand (FH) group and 12 patients in the guide group). The major perforation rate was significantly lower in the guide group than in the FH group (2.1% vs. 9.1%, p < 0.001). Significantly fewer major perforations were observed in the guide group than in the FH group in the upper thoracic (T2-4) region (3.2% vs. 20%, p < 0.001) and lower thoracic (T10-12) region (0% vs. 13.8%, p = 0.001). The operative time, EBL, and correction rate were equivalent between the two groups. CONCLUSION: The 3D-printed patient-specific guide notably reduced the major perforation rate of PS without increasing EBL and operative time. Our findings indicate that this guide system is reliable and effective for AIS surgery.

Efficacy of Anterior Quadratus Lumborum Block and Pain After Total Hip Arthroplasty: A Randomized Controlled Trial.

BACKGROUND: Anterior quadratus lumborum block (AQLB) is one of the compartment blocks and has recently attracted attention as a new method of analgesia for postoperative hip surgery analgesia. This study aimed to compare the analgesic efficacy of AQLB in patients undergoing primary total hip arthroplasty (THA). METHODS: There were 120 patients undergoing primary THA under general anesthesia randomly allocated to receive a femoral nerve block (FNB) or an AQLB. The primary outcome was total morphine consumption over the initial 24-hour postoperative period. Secondary outcomes included the pain score evaluation while at rest and during active and passive motion over the 2 days following surgery and the manual muscle testing of the quadriceps femoris. The numerical rating scale (NRS) score was used for evaluating the postoperative pain score. RESULTS: There were no significant differences between the 2 groups concerning morphine consumption within 24 hours after surgery (P = .72). The NRS score at rest and passive motion were similar at all-time points (P > .05). However, there was a statistically significant difference in pain reported during the active motion for the FNB group compared to the AQLB (P = .04). No significant differences were found between the 2 groups concerning muscle weakness incidence. CONCLUSION: Both AQLB and FNB demonstrated adequate efficacy for postoperative analgesia at rest in THA. However, based on our study, whether AQLB is inferior or noninferior to FNB as an analgesic method for THA was inconclusive.

Adjacent vertebral Hounsfield unit value of acute osteoporotic vertebral fracture is a risk factor for concomitant domino osteoporotic vertebral fractures.

BACKGROUND: Most patients with acute osteoporotic vertebral fracture (AOVF) are successfully treated conservatively. However, the optimal management method and prognosis for multiple AOVFs are unclear. This study aimed to investigate the prevalence of multiple AOVFs and identify the associated risk factors. METHODS: This study enrolled 134 hospitalized patients (mean age 83 ± 7.6 years, 66% women) with AOVF treated conservatively between 2017 and 2020. The fractures were diagnosed by magnetic resonance imaging (MRI). The AOVFs were divided into two groups; single osteoporotic vertebral fractures (OVF) and domino OVFs (at least two OVFs). The adjacent vertebral Hounsfield unit values (HU) of the OVF and dual x-ray absorptiometry (DXA) of the lumbar spine or hip were used to evaluate the bone mineral density (BMD). Logistic regression analysis was performed to identify the risk factors for domino OVFs. RESULTS: Domino OVFs were noted in 21 (15.7%) of 134 patients. There were 10 cases of adjacent level and 11 cases of remote level. The BMI (18.5 ± 4.2 vs. 21.2 ± 4.6, p = 0.025) and adjacent vertebral HU value of OVF (57.3 ± 17.5 vs. 76.6 ± 24.1, p = 0.008) were significantly lower in the domino OVFs group than in the single OVF group. Logistic regression analysis revealed the adjacent vertebral HU value of the OVF as an independent risk factor for domino OVFs, (odds ratios (OR) 0.96, p = 0.012). The domino OVF group had a significantly higher decline in gait ability (76% vs. 48%, p = 0.017). CONCLUSIONS: The adjacent vertebral HU value of AOVF is a useful tool for evaluating BMD for domino OVFs. The optimal treatment for osteoporosis should be considered to prevent subsequent domino OVFs.

Osteoscopic versus open surgery for the treatment of enchondroma in the foot.

INTRODUCTION: The conventional treatment of enchondromas is the open surgery with curettage of lesions. Osteoscopic surgery is a minimally invasive endoscopic approach for lesions inside bone. The aim of this study was to evaluate the feasibility of the osteoscopic surgery in comparison with the conventional open surgery for patients with foot enchondromas. MATERIALS AND METHODS: A retrospective cohort study comparing patients with foot enchondromas treated with osteoscopic or open surgery from 2000 to 2019. Functional evaluations were based on both the AOFAS score and the Musculoskeletal Tumor Society (MSTS) functional rate. Complication and local recurrence were evaluated. RESULTS: Seventeen patients underwent endoscopic surgery, and eight patients underwent open surgery. The AOFAS score was higher in the osteoscopic group than the open group at 1 and 2 weeks after surgery (mean, 89.18 vs 67.25 [p = 0.001], 93.88 vs 79.38 [p = 0.004]). The MSTS functional rate was also higher in the osteoscopic group than the open group at 1 and 2 weeks after surgery (mean, 81.96 vs 59.58% [p = 0.00], 90.98 vs 75.00% [p = 0.02]). No statistical differences were found after 1-month of surgery. The osteoscopic group had lower complication rate than the open group (12 vs 50%; p = 0.04). No local recurrence was found in any groups. CONCLUSION: The osteoscopic surgery is feasible to provide earlier functional recovery and fewer complications than the open surgery.

The Relationship between the Hounsfield Units Value of the Upper Instrumented Vertebra and the Severity of Proximal Junctional Fracture after Adult Spinal Deformity Surgery.

Background and Objectives: In this retrospective cohort study, we investigate associations between the Hounsfield units (HU) value of upper instrumented vertebra (UIV) and proximal junctional kyphosis (PJK) after adult spinal deformity (ASD) surgery. Materials and Methods: The cohort consisted of 60 patients (mean age 71.7 years) who underwent long instrumented fusion surgery (≥6 vertebrae) for ASD with at least 1 year of follow-up. The preoperative bone mineral density (BMD) measured on DXA scans, the HU values at UIV and UIV+1, and the radiographic parameters were compared between the PJK and non-PJK groups. The severity of UIV fracture was assessed using a semiquantitative (SQ) grade. Results: PJK occurred in 43% of patients. No significant differences in patient age, sex, BMD, and preoperative radiographic parameters were observed between the PJK and non-PJK groups. The HU values of the UIV (103.4 vs. 149.0, p < 0.001) and UIV+1 (102.0 vs. 145.7, p < 0.001) were significantly lower in the PJK group. The cutoff values of HU at UIV and UIV+1 were 122.8 and 114.9, respectively. Lower HU values at UIV (Grade 1: 134.2, Grade 2: 109.6, Grade 3: 81.1, p < 0.001) and UIV+1 (Grade 1: 131.5, Grade 2: 107.1, Grade 3: 82.1, p < 0.001) were associated with severe SQ grade. Conclusions: Lower HU values at UIV and UIV+1 had a negative impact on signal incidence of PJK and were correlated with the severity of UIV fractures. Preoperative treatment of osteoporosis seems necessary for preoperative UIV HU values less than 120.

Subsequent Domino Osteoporotic Vertebral Fractures Adversely Affect Short-Term Health-Related Quality of Life: A Prospective Multicenter Study.

Background and Objectives: Conservative treatment is the gold standard for acute osteoporotic vertebral fractures (AOVFs). However, the treatment strategy for multiple AOVFs remains unknown. We conducted a prospective study using magnetic resonance imaging (MRI) to investigate how rapidly subsequent osteoporotic vertebral fractures (OVFs) occur as domino OVFs within 3 months. This study aimed to assess the incidence and impact of domino OVFs on quality of life (QOL) following conservative treatment for initial AOVFs. Materials and Methods: A prospective multicenter cohort study was conducted at eight hospitals. The included patients were those with AOVFs occurring within 3 weeks, aged >60 years, and diagnosed using MRI. All patients were treated conservatively and underwent MRI after 3 months. Subsequent domino OVFs were defined as newly occurring OVFs within 3 months. Patient characteristics, types of conservative treatment, and patient-reported outcomes, including a visual analogue scale (VAS), the Oswestry disability index (ODI), and the Japanese Orthopaedic Association back pain evaluation questionnaire (JOABPEQ), were evaluated and compared between the domino OVF and non-domino OVF groups. Results: A total of 227 patients were analyzed. The mean age was 80.1 ± 7.3 years and 78% were female. Subsequent domino OVFs were observed in 31 (13.6%) patients within 3 months. An increasing number of prevalent OVFs were significantly associated with domino OVFs (p = 0.01). No significant differences in bone mineral density, type of brace, and anti-osteoporosis medications were found between the two groups. The JOABPEQ (excluding social function), ODI, and VAS were significantly improved after 3 months. Patients with domino OVFs at 3 months had poorer JOABPEQ social life function, ODI, and VAS than those with non-domino OVFs. Conclusions: In this study, the incidence of domino OVFs was 13.6% within 3 months. Domino OVFs had a negative impact on QOL at 3 months and were associated with prevalent OVFs.

The Impact of Controlling Nutritional Status (CONUT) score on functional prognosis in hospitalized elderly patients with acute osteoporotic vertebral fractures.

BACKGROUND: Nutritional status, which is associated with osteoporosis and muscle weakness is considered an important factor in the management of acute osteoporotic vertebral fracture (AOVF). However, few reports have investigated the nutritional status of hospitalized patients with AOVF and the impact of malnutrition on their functional prognosis. This study aimed to evaluate the nutritional status of hospitalized elderly patients with AOVF using the Controlling Nutritional Status (CONUT) score and to determine the usefulness of the CONUT score in predicting their functional prognosis. METHODS: The CONUT score on admission was retrospectively calculated for 134 hospitalized elderly patients (mean age 83 ± 7.6 years, 66% female) with AOVF who received conservative treatment between 2017 and 2020. Functional outcome was assessed by comparing ambulatory ability before the onset of AOVF and upon discharge. Patients were divided into two groups: CONUT-high ( ≥ 4) and CONUT-low ( ≤ 3), according to receiver operating characteristic (ROC) analysis to predict decline in ambulatory ability upon discharge. Logistic regression analysis was performed to obtain odds ratios (OR) and 95% confidence intervals (CI) of the relationships between the nutritional status and ambulatory ability. The discriminative power of the CONUT score was then compared with other nutritional assessment tools such as the Geriatric Nutritional Risk Index (GNRI) and prognostic nutritional index (PNI) by ROC analysis. RESULTS: 81% of hospitalized patients with an AOVF were malnourished at the time of admission. The CONUT-high group had a significantly higher rate of decline in ambulatory ability (P < 0.001) than the CONUT-low group. Logistic regression analysis revealed the CONUT score ( ≥ 4) as an independent risk factor for a decline in ambulatory ability (OR 3.44, 95% CI 1.61-7.37, P = 0.0014). ROC analysis showed that the area under the curve (AUC) for the CONUT score (AUC = 0.724) was significantly greater than that for the GNRI (AUC = 0.624, P = 0.021) and PNI (AUC = 0.636, P = 0.0008). CONCLUSIONS: This study showed that 81% of hospitalized elderly patients with AOVFs were malnourished and that the CONUT score was a useful predictive factor of functional prognosis.

Long term results of the Bicontact D stem in dysplastic osteoarthritis: a 10-15 year follow-up study.

PURPOSE: The purpose of the present study was to investigate the results of total hip arthroplasty (THA) using the Bicontact D stem with a minimum 10 year follow-up that focused on patients with developmental dysplasia of the hip (DDH). METHODS: One hundred five patients with osteoarthritis due to DDH who underwent primary THA were included in this study. The mean final follow-up period was 12.7 ± 1.2 years (range 10-15 years). All cases were evaluated both clinically and radiographically, and Kaplan-Meier survivorship was determined as stem revision for any reason as the end point. RESULTS: Modified Harris hip score averaged 89.0 ± 1.1 (range 60-98) at the final follow-up. The survivorship was 99.0% (95% confidence interval 93.4-99.9%) at 15.0 years, and only one hip with a well-fixed stem required stem revision due to recurrent dislocations. Cortical hypertrophy (CH) was observed in 40 of 105 hips (38.1%), and stress shielding (SS) progressed to grade 3 or 4 in six hips (6 of 105 hips: 5.7%) during the study period. Among the six hips with progressed SS, Dorr type C proximal femoral geometry was seen in five hips. CONCLUSION: This study of 105 THAs using the Bicontact D stem that focused on DDH patients with a minimum 10 year follow-up period achieved satisfactory clinical and radiological outcomes. Dorr type C proximal femoral geometry could be considered a risk factor for progressed SS.

Incidence of and risk factors for deep vein thrombosis in patients undergoing osteotomies around the knee: comparative analysis of different osteotomy types.

PURPOSE: To examine the incidence of and risk factors for deep vein thrombosis (DVT) among different types of osteotomies around the knee. It was hypothesized that DVT would be detected at a substantial rate after the osteotomy, and there would be differences in the incidences among the different osteotomy procedures. METHODS: Consecutive patients who underwent knee osteotomies for varus osteoarthritis and met the inclusion criteria were included in the study. Ultrasonographic evaluation was performed to detect DVT on bilateral whole leg at 1 month before and 7 days after surgery. Statistical comparison of the demographic and clinical parameters between the patients with and without DVT as well as multivariate analysis using logistic regression was conducted to identify risk factors related to the incidence of postoperative DVT. RESULTS: The study subjects comprised 159 knees in 135 patients with medial opening wedge high tibial osteotomy (MOW-HTO), 93 knees in 78 patients with lateral closed wedge high tibial osteotomy (LCW-HTO), and 74 knees in 54 patients with double level osteotomy (DLO). In the postoperative evaluation, DVT was detected in 19 of 159 knees (11.9%) in MOW-HTO, 21 of 93 knees (22.6%) in LCW-HTO, and 5 of 74 knees (6.8%) in DLO. The incidence of DVT was significantly higher after LCW-HTO than after MOW-HTO and DLO (p < 0.01). DVT at a level above the knee was noted in one case after MOW-HTO, while DVT in the remaining cases developed at a level below the knee. No cases of symptomatic pulmonary embolism were encountered during the study period. Among the potential risk factors assessed for correlation with the incidence of DVT, LCW-HTO was identified as a significant risk factor (odds ratio: 2.54; 95% CI 1.334-4.836; p < 0.01). CONCLUSIONS: This study demonstrated that DVT occurred at a substantial rate (overall incidence of 13.8%) after osteotomy around the knee even with the use of prophylactic anticoagulant. Among the different osteotomy types, the DVT rate was significantly higher after LCW-HTO than after MOW-HTO and DLO. LEVEL OF EVIDENCE: Prospectively designed observational cohort study, Level III.

Return to sports rate after opening wedge high tibial osteotomy in athletes.

PURPOSE: We hypothesized that patient treated with OWHTO who participate in high-impact sports would attain satisfactory outcome. The purpose of this study was to examine the clinical and radiological outcomes in a consecutive series of opening-wedge high tibial osteotomy (OWHTO) in highly active patients. METHODS: Seventy-seven consecutive patients who underwent OWHTO with varus osteoarthritic knees were included in the study. The mean age of the study population was 56.1 years. All patients were followed for a minimum of 2 years. Clinical and radiological evaluations were performed at 12 and 24 months after surgery. The clinical results were evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee (IKDC) Subjective Score. In regards to radiological assessment, the following parameters were measured in full-length weightbearing radiographs both pre- and postoperatively; mechanical tibiofemoral angle (mTFA), mechanical lateral distal femoral angle (mLDFA), and weight bearing line (WBL) ratio. RESULTS: Fifty-eight patients (75.3%) returned to the same high-impact sports activities as before surgery, with a mean time to return of 8.7 ± 2.7 months (6-14 months). In the clinical assessments, the IKDC subjective score and KOOS both improved from the mean preoperative scores of 38.4 and 217.4 points to the mean postoperative scores of 74.5 and 421.6 points, respectively. The mean pre-symptomatic Tegner activity scale was 5.3 ± 0.6 and significantly decreased to 4.8 ± 1.2 at 2 years postoperative (p < 0.05). In the radiological evaluation, the postoperative mTFA, mMPTA, and WBL ratio values averaged 1.3° ± 2.2° valgus, 90.7° ± 2.9°, and 51.6% ± 8.4°, respectively, at 24 months after surgery. CONCLUSIONS: Clinical outcomes based on postoperative patient-reported outcome measures and rate of return to high-impact sports activities were favorable after OWHTO in patients with knee OA who desired to continue sporting activities with the Tegner activity score of ≥ 5 points. LEVEL OF EVIDENCE: Retrospective case series, IV.

Hinge fracture in lateral closed-wedge distal femoral osteotomy in knees undergoing double-level osteotomy: assessment of postoperative change in rotational alignment using CT evaluation.

PURPOSE: The purpose of this study was to examine the radiological features of hinge fracture occurring at the distal medial femoral cortex in knees undergoing biplanar lateral closed-wedge distal femoral osteotomy (LCW-DFO) in double-level osteotomy (DLO) based on pre- and postoperative CT image analyses. It was hypothesised that medial hinge fractures in LCW-DFO would occur with a similar incidence to that in high tibial osteotomy, and its occurrence would affect the clinical/radiological outcomes and induce unintended change in alignment depending on the fracture type (direction of the fracture). METHODS: A consecutive series of 36 knees (31 patients) with primary varus osteoarthritis undergoing DLO comprised the study population. The mean age at surgery was 62.0 ± 5.9 years. Presence of hinge fracture was assessed on radiographs and CT images at 1 week. The fracture type was classified depending on the direction of the fracture line: crack propagation in line with the osteotomy (type 1) and fractures extending proximally (type 2) or distally (type 3) from the tip of the wedge. Computer-assisted assessments of bony limb alignment and bony geometry were conducted on a full-length weight-bearing radiograph and CT images using image analysis software. In addition, subjective clinical results were evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS). Radiological and clinical follow-up results at 1 and 2 years were compared to the preoperative data, while comparative analysis was made between the subjects with and without a hinge fracture. RESULTS: Postoperative image examinations revealed type 1 and 2 medial femoral hinge fractures in 4 and 7 knees, while no type 3 fracture was identified in the study population. Consequently, the overall incidence of the hinge fracture was 30.6% (11 of the 36 knees). Four of those 11 fractures (36.4%) could not be detected on plain radiographs. CT image analysis for three-dimensional bony geometry showed greater increase in internal rotation of the distal bony segment (increased femoral antetorsion by 9.5° on average) after surgery compared to the knees without a hinge fracture (P = 0.01). Clinical evaluation using the KOOS at 2 years showed no significant difference between the groups with and without hinge fractures. CONCLUSION: In LCW-DFO, medial femoral hinge fractures occurred in 30.6% of the cases. Knees with type 1 hinge fracture exhibited significantly greater increase in femoral antetorsion as compared to those without hinge fracture. In this case series, postoperative weight-bearing protocol was delayed for knees with hinge fracture. Consequently, surgical results were not affected by the occurrence of hinge fracture for up to 2 years. LEVEL OF EVIDENCE: IV (case series).

Quantitative bone SPECT/CT applications for primary bone neoplasms.

OBJECTIVE: To evaluate the clinical utility of quantitative values obtained with bone single photon emission computed tomography/computed tomography (SPECT/CT) for primary bone neoplasms. SUBJECTS AND METHODS: Bone SPECT/CT scans of 23 patients with 19 benign bone neoplasms (5 osteoid osteomas, 4 bone giant cell tumor, 4 osteofibrous dysplasia, 3 intraosseous ganglion, 2 aneurysmal bone cyst, 1 intraosseous hemangioma) and 5 malignant bone neoplasms (2 osteosarcoma, 1 periosteal osteosarcoma, 1 malignancy in bone giant cell tumor, 1 Ewing sarcoma) were retrospectively analyzed with maximum standardized uptake value (SUVmax), peak SUV (SUVpeak), mean SUV (SUVmean), metabolic bone volume (MBV), and total bone uptake (TBU) of primary lesions. RESULTS: Mean SUVmax of 19 benign and 5 malignant primary bone neoplasms were 6.89±3.26 (range 3.9-15.13) and 10.31±3.19 (5.0-13.45) respectively, with statistically significant difference (P=0.048). Mean SUVpeak of those were 5.87±2.83 (range 3.5-13.63) and 9.18±3.05 (4.09-12.03) respectively, with statistically significant difference (P=0.032). Mean SUVmean of those were 4.43±2.11 (range 2.59-9.37) and 7.13±2.90 (3.3-10.42) respectively, with statistically significant difference (P=0.027). Mean MBV of those were 22.0±30.0 (range 2.47-110.61) and 27.8±39.94 (8.59-99.24) respectively, with no statistically significant difference (P=0.72). Mean TBU of those were 80.64±94.57 (range 10.50-373.57) and 166.60±203.97 (28.68-528.13) respectively, with no statistically significant difference (P=0.17). CONCLUSION: Quantitative values obtained with bone SPECT/CT may serve as osteoblastic biomarkers for primary bone neoplasm.

Quantitative bone SPECT/CT applications for cartilaginous bone neoplasms.

OBJECTIVE: To evaluate the ability of quantitative values obtained with bone single photon emission computed tomography/computed tomography (SPECT/CT) to differentiate benign from malignant cartilaginous bone neoplasms. SUBJECTS AND METHODS: Bone SPECT/CT scans of 10 patients with 8 benign cartilaginous bone neoplasms (4 enchondromas, 1 periosteal chondroma, 1 osteochondroma, 1 bizarre parosteal osteochondromatous proliferation, 1 chondroblastoma) and 2 malignant cartilaginous bone neoplasms (1 periosteal chondrosarcoma, 1 chondrosarcoma) were retrospectively analyzed with maximum standardized uptake value (SUVmax), mean SUV (SUVmean), metabolic bone volume (MBV), and total bone uptake (TBU) of primary lesions. RESULTS: Mean SUVmax of 8 benign and 2 malignant cartilaginous bone neoplasms were 1.93±1.02 (range 0.59-3.41) and 6.07±0.86 (5.46-6.67), respectively with no overlap (P=0.028). Mean SUVmean of those were 1.24±0.71 (range 0.36-2.36) and 4.05±0.30 (3.84-4.26), respectively with no overlap (P=0.00036). Mean MBV of those were 7.17±4.19 (range 3.17-13.77) and 10.29±10.05 (3.19-17.4), respectively with no significant difference (P=0.74). Mean TBU of those were 9.22±8.31 (range 1.15-23.61) and 43.19±43.7 (12.26-74.13), respectively with no significant difference (P=0.47). CONCLUSION: Standardized uptake value obtained with bone SPECT/CT may be useful to differentiate benign from malignant cartilaginous bone neoplasms, thus helping the orthopedic surgeon towards the most appropriate treatment procedure.

Achievement of optimal implant alignment using taper wedge stems with cup-first THA through the MIS antero-lateral approach.

PURPOSE: Combined anteversion (CA) technique (stem-first procedure) has become generally accepted as an ideal means to achieve optimal CA value in THA. However, we hypothesized that CA technique for patients with various native femoral anteversions could pose a risk of anterior or posterior cup protrusion. In the present study, we examined whether it is possible to use the taper wedge stem to change the stem version to achieve optimal CA while avoiding cup protrusions with the cup-first procedure through minimally invasive (MIS) antero-lateral approach. METHODS: Eighty-one patients underwent cup-first THA with a taper wedge stem. The acetabular cup was placed following the preoperative planning of the cup alignment to avoid anterior cup protrusions using CT-based navigation. Following the CA theory, anteversion of the taper wedge stem was changed to the target anteversion from the patient's native femoral anteversion. The native femoral anteversion, the change in version angle of the stem, postoperative CA and the length of anterior cup protrusions were evaluated in postoperative CT measurements. RESULTS: The native femoral anteversion averaged 25.7° ± 8.9° (range 8°-45°). Cases with increased and decreased stem anteversion were observed in 42 hips (51.8%) and 33 hips (40.7%), respectively. The amount of increased and decreased version angles averaged 7.7° ± 4.8° (range 2°-21°) and 7.8° ± 5.1° (range 2°-20°), respectively. Postoperative CA values averaged 36.7° ± 3.4° (range 29.4°-44.2°) and anterior cup protrusion length averaged 2.0 mm ± 2.6 mm (0 ~ 8.8 mm) in axial view and 0.4 mm ± 1.0 mm (0 ~ 3.6 mm) in sagittal view. Anterior cup protrusion of more than 10 mm was not observed in any hips. CONCLUSION: This procedure can be considered as an option to achieve optimal CA anteversion while avoiding anterior cup protrusion in THA.

Clinical outcomes after posterior cervical decompression and fusion surgery for destructive spondyloarthropathy in patients undergoing long-term hemodialysis: A matched case-control study.

BACKGROUND: Cervical destructive spondyloarthropathy (DSA) often leads to cervical myelopathy in long-term hemodialysis patients. However, the surgical outcomes after instrumented fusion surgery for cervical DSA are still unclear. The objective of this study was to investigate the clinical outcomes of cervical DSA in comparison with a control group. MATERIALS AND METHODS: A consecutive series of 20 undergoing long-term hemodialysis patients who underwent instrumented fusion surgery for cervical DSA between 2010 and 2016 were included in this study (DSA group). The mean age at surgery was 65 years, and there were 11 men and 9 women. The average length of hemodialysis was 23 years. The age- and sex-matched control group consisted of 20 patients (degenerative conditions). The Japanese Orthopedic Association (JOA) score, recovery rate, complications, and loss of correction of fused level were compared between the groups. RESULTS: Two of the 20 patients died due to perioperative complications. More than 1 year of follow-up data after surgery was available for 18 patients. The mean JOA score significantly increased from 5.4 before surgery to 9.7 at 1 year after surgery and 8.3 at the final follow-up (mean: 33.2 ± 21.3 months, P = 0.019). There were no significant differences in the mean recovery rate (41% vs. 37%, P = 0.44) between the DSA group and control group. Loss of correction of more than 5°was significantly higher in the DSA group (44% vs. 10%, P = 0.027). The rate of pseudarthrosis (17% vs. 5%, P = 0.328) and adjacent segment disease (22% vs. 10%, P = 0.17) tended to be higher in the DSA group. DISCUSSION: The clinical outcomes showed significant recovery in both groups. Therefore, posterior cervical decompression and fusion surgery was effective for treating cervical DSA.

Comparison of the AOSpine subaxial cervical spine injury classification system and the Allen classification.

The AOSpine group has launched a new subaxial cervical spine injury system (AOSCIS) based on morphology. The objective of this study was to use the AOSCIS and compare it to the widely used Allen classification (AC) based on mechanics for subaxial cervical spine injury. Twenty-two consecutive patients with subaxial cervical spine injury who received posterior cervical fixation in our hospital were included in this study. Medical records were evaluated retrospectively. The evaluated factors were as follows: preoperative ASIA impaired scale (AIS), AOSCIS, AC, and diffuse idiopathic skeletal hyperostosis (DISH). There was AIS A in nine patients, AIS C in four patients, AIS D in four patients, and AIS E in five patients. Two patients with AOSCIS B2 were classified as AC DF1. Two AOSCIS F3 patients were classified as AC CE1. Eighteen AOSCIS C patients were classified into multiple categories: five as AC DF2, three as DF3, one as CF4, one as CF5, four as DE2, three as CE3 + DE1, and one as CE3 + VC2. All of the AOSCIS A0 (F) or B patients were classified as AC stage 1, and all of the AOSCIS C patients were classified as AC stage 2 and higher (P < 0.05). All of six patients with DISH were classified as AOSCIS C and CE3, DE2, or DF3. AOSCIS and AC are correlated. Conducting an evaluation using both systems helps us to better comprehend subaxial cervical spine injuries.

Prognosis and adjacent segment disease after lumbar spinal fusion surgery for destructive spondyloarthropathy in long-term hemodialysis patients.

BACKGROUND: Lumbar destructive spondyloarthropathy (DSA) is a serious complication in long-term hemodialysis patients. There have not been many reports regarding the surgical management for lumbar DSA. In addition, the adjacent segment pathology after lumbar fusion surgery for DSA is unclear. The objective of this study was to assess the clinical outcome and occurrence of adjacent segmental disease (ASD) after lumbar instrumented fusion surgery for DSA in long-term hemodialysis patients. MATERIALS AND METHODS: A consecutive series of 36 long-term hemodialysis patients who underwent lumbar instrumented fusion surgery for DSA were included in this study. The mean age at surgery was 65 years. The mean follow-up period was 4 years. Symptomatic ASD was defined as symptomatic spinal stenosis or back pain with radiographic ASD. The Japanese Orthopedic Association score (JOA score), recovery rate (Hirabayashi method), complications, and reoperation were reviewed. RESULTS: The mean JOA score significantly increased from 13.5 before surgery to 21.3 at the final follow-up. The mean recovery rate was 51.4%. Six of the 36 patients died within 1 year after index surgery. One patient died due to perioperative complication. Symptomatic ASD occurred in 43% (13 of 30) of the cases. Of these 13 cases, 5 had adjacent segment disc degeneration and 8 had adjacent segment spinal stenosis. Three cases (10%) required reoperation due to proximal ASD. Multi-level fusion surgery increased the risk of ASD compared with single-level fusion surgery (59% vs. 23%). The recovery rate was significantly lower in the ASD group than the non-ASD group (38% vs. 61%). DISCUSSION: This study demonstrated that symptomatic ASD occurred in 43% of patients after surgery for lumbar DSA. A high mortality rate and complication rate were observed in long-term hemodialysis patients. Therefore, care should be taken for preoperative planning for surgical management of DSA.