Microvascular changes are considered key factors in the process of intervertebral disk degeneration (IDD). Microvascular invasion and growth into the nucleus pulposus (NP) and cartilaginous endplates are unfavorable factors that trigger IDD. In contrast, the rich distribution of microvessels in the bony endplates and outer layers of the annulus fibrosus is an important safeguard for the nutrient supply and metabolism of the intervertebral disk (IVD). In particular, the adequate supply of microvessels in the bony endplates is the main source of the nutritional supply for the entire IVD. Microvessels can affect the progression of IDD through a variety of pathways. Many studies have explored the effects of microvessel alterations in the NP, annulus fibrosus, cartilaginous endplates, and bony endplates on the local microenvironment through inflammation, apoptosis, and senescence. Studies also elucidated the important roles of microvessel alterations in the process of IDD, as well as conducted in-depth explorations of cytokines and biologics that can inhibit or promote the ingrowth of microvessels. Therefore, the present manuscript reviews the published literature on the effects of microvascular changes on IVD to summarize the roles of microvessels in IVD and elaborate on the mechanisms of action that promote or inhibit de novo microvessel formation in IVD.

Chronic lateral epicondylitis (LE), normally known as tennis elbow, is often managed by conservative treatments. Extracorporeal shock wave therapy (ESWT) and local corticosteroid injection (LCI) are among the most commonly used conservative treatments. However, the comparison between these two interventions remains controversial. This study aimed to compare the effectiveness and safety of ESWT and LCI for chronic LE. A systematic review and meta-analysis was conducted following the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) guidelines. PubMed, EMBASE, Cochrane Library, and Web of Science were searched for eligible studies until April 20, 2024. Meta-analyses were conducted using Manager V.5.4.1. Pooled effect sizes were expressed as the weighted mean difference (WMD) or odds ratio (OR), with 95% confidence intervals (CIs). A total of six randomized controlled trials (RCTs) were included. Compared with LCI, ESWT had inferior change in visual analogue scale (Δ VAS) (WMD, 1.14; 95% CI, 0.80 to 1.48; I² = 20%; p < 0.001), Δ grip strength (WMD, –4.01; 95% CI, –5.57 to –2.44; I² = 36%; p < 0.001), change in patient-rated tennis elbow evaluation (Δ PRTEE) score (WMD, 8.64; 95% CI, 4.70 to 12.58; I² = 0%; p < 0.001) at 1-month follow-up, but superior Δ VAS (WMD, –1.15; 95% CI, –1.51 to –0.80; I² = 6%; p < 0.001), Δ grip strength (WMD, 2.04; 95% CI, 0.90 to 3.18; I² = 3%; p = 0.0005), Δ PRTEE score (WMD, –9.50; 95% CI, –14.05 to –4.95; I² = 58%; p < 0.001) at 3-month follow-up, and superior Δ VAS (WMD, –1.81; 95% CI, –2.52 to –1.10; I² = 33%; p < 0.001), Δ grip strength (WMD, 3.06; 95% CI, 0.90 to 5.21; I² = 0%; p = 0.005) at 6-month follow-up. The two groups had a similarly low rate of adverse events (OR, 0.69; 95% CI, 0.05 to 8.60; I² = 67%; p = 0.77), all of which were mild. Both ESWT and LCI are effective and safe in treating chronic LE. Compared with LCI, ESWT showed inferior short-term (1-month) but superior long-term (3-month and 6-month) outcomes regarding pain relief and function recovery, with a similar rate of mild adverse events.

Total knee arthroplasty (TKA) is a well-established treatment for end-stage knee osteoarthritis. However, in patients with concomitant extra-articular deformities, conventional TKA techniques may lead to unsatisfactory outcomes and higher complication rates. This review summarizes the application of navigated TKA for treating knee osteoarthritis with extra-articular deformities. The principles and potential benefits of computer navigation systems, including improved component alignment, soft tissue balancing, and restoration of mechanical axis, are discussed. Research studies demonstrate that navigated TKA can effectively correct deformities, relieve pain, and improve postoperative joint function and quality of life compared with conventional methods. The advantages of navigated TKA in terms of surgical precision, lower complication rates, and superior functional recovery are highlighted. Despite challenges like the learning curve and costs, navigated TKA is an increasingly indispensable tool for achieving satisfactory outcomes in TKA for knee osteoarthritis patients with extra-articular deformities.

The increasing frequency of cervical and lumbar spine disorders, driven by aging and evolving lifestyles, has led to a rise in spinal surgeries using pedicle screws. Robotic spinal surgery systems have emerged as a promising innovation, offering enhanced accuracy in screw placement and improved surgical outcomes. We focused on literature of this field from the past 5 years, and a comprehensive literature search was performed using PubMed and Google Scholar. Robotic spinal surgery systems have significantly impacted spinal procedures by improving pedicle screw placement accuracy and supporting various techniques. These systems facilitate personalized, minimally invasive, and low-radiation interventions, leading to greater precision, reduced patient risk, and decreased radiation exposure. Despite advantages, challenges such as high costs and a steep learning curve remain. Ongoing advancements are expected to further enhance these systems’ role in spinal surgery.

Objective: As the population ages and technology advances, lateral lumbar intervertebral fusion (LLIF) is gaining popularity for the treatment of degenerative lumbar scoliosis (DLS). This study investigated the feasibility, minimally invasive concept, and benefits of LLIF for the treatment of DLS by observing and assessing the clinical efficacy, imaging changes, and complications following the procedure.

Methods: A retrospective analysis was performed for 52 DLS patients (12 men and 40 women, aged 65.84 ± 9.873 years) who underwent LLIF from January 2019 to January 2023. The operation time, blood loss, complications, clinical efficacy indicators (visual analogue scale [VAS], Oswestry disability index [ODI], and 36-Item Short Form Survey), and imaging indicators (coronal position: Cobb angle and center sacral vertical line–C7 plumbline [CSVL–C7PL]; and sagittal position: sagittal vertical axis [SVA], lumbar lordosis [LL], pelvic incidence angle [PI], and thoracic kyphosis angle [TK] were measured). All patients were followed up. The above clinical evaluation indexes and imaging outcomes of patients postoperatively and at last follow-up were compared to their preoperative results.

Results: Compared to the preoperative values, the Cobb angle and LL angle were significantly improved after surgery (p < 0.001). Meanwhile, CSVL–C7PL, SVA, and TK did not change much after surgery (p > 0.05) but improved significantly at follow-up (p < 0.001). There was no significant change in PI at either the postoperative or follow-up timepoint. The operation took 283.90 ± 81.62 min and resulted in a total blood loss of 257.27 ± 213.44 mL. No significant complications occurred. Patients were followed up for to 21.7 ± 9.8 months. VAS, ODI, and SF-36 scores improved considerably at postoperative and final follow-up compared to preoperative levels (p < 0.001). After surgery, the Cobb angle and LL angle had improved significantly compared to preoperative values (p < 0.001). CSVL–C7PL, SVA, and TK were stable after surgery (p > 0.05) but considerably improved during follow-up (p < 0.001). PI showed no significant change at either the postoperative or follow-up timepoints.

Conclusion: Lateral lumbar intervertebral fusion treatment of DLS significantly improved sagittal and coronal balance of the lumbar spine, as well as compensatory thoracic scoliosis, with good clinical and radiological findings. Furthermore, there was less blood, less trauma, and quicker recovery from surgery.

Purpose: Arthroscopic Bankart repair combined with remplissage and autologous scapular spine bone grafting have been described as a treatment for off-track Hill–Sachs lesions with subcritical glenoid bone defects in the anterior shoulder instability. However, whether these two techniques can achieve satisfactory postoperative outcomes is unclear, and there are few comparative studies between them. Therefore, this study compared the postoperative efficacy of the two techniques for off-track Hill–Sachs lesions with subcritical glenoid bone loss.

Method: Between June 2017 and December 2020, 62 patients with shoulder instability due to Off-Track Hill–Sachs lesions with subcritical glenoid bone loss underwent surgical treatment and were included in this regression study. Thirty-two patients underwent arthroscopic Bankart repair combined with remplissage (B + R group), and 30 patients underwent additional autologous scapular glenoid bone grafting (additional bone grafting group). The general information of the patients was recorded. The patient’s activity before and after surgery was recorded. The DASH score and Constant–Murley (CM) score were used to assess the patient’s functional status; the Rowe score was used to evaluate the patient’s shoulder stability. The shoulder function and stability before and after surgery were analyzed and compared between the two groups.

Results: The final DASH scores of the B + R group and the additional bone grafting group were significantly lower than those before surgery, with a statistically significant difference (9.76 ± 4.32 vs. 27.89 ± 6.63, 8.50 ± 3.32 vs. 28.0 ± 4.27, p = 0.000); the final CM scores of the two groups were significantly higher than those before surgery (88.71 ± 3.74 vs. 73.68 ± 3.74, 87.16 ± 2.29 vs. 71.37 ± 2.68, p = 0.000). There was no statistical difference in the final DASH score and final CM score between the two groups (p > 0.05). In terms of postoperative stability, the final Rowe scores of the two groups were significantly higher than those before surgery, with a statistically significant difference (89.06 ± 9.19 vs. 41.71 ± 4.13; 93.16 ± 4.99 vs. 42.33 ± 2.53, p = 0.000). Compared with the control group, the additional bone graft group achieved higher final Rowe scores (93.16 ± 4.99 vs. 89.06 ± 9.19, p = 0.032).

Conclusion: For patients with anterior shoulder instability due to off-track Hill–Sachs lesions with subcritical glenoid bone loss, although Bankart and remplissage can achieve satisfactory clinical results, additional autogenous scapular spine bone grafting can provide better stability of the shoulder, especially for patients with high sports demands.

Objective: Lower limb discrepancy (LLD) was frequently observed in patients with idiopathic scoliosis (IS), potentially associated with etiopathogenesis. Although sole lifts had been proposed as a conservative treatment for IS, evidence supporting their efficacy was limited. This study aimed to assess the effects of sole lift intervention on pediatric patients with mild IS, specifically focusing on thoracolumbar/lumbar (TL/L) curvature.

Methods: Twenty patients, with an average age of 12.3 ± 3.1 years and presenting mild TL/L curve (15.6° ± 6.2°), were selected from a pool of 267 pediatric IS patients in the outpatient of our spine center from February 2023 to August 2023. Inclusion criteria comprised a main TL/L curve ranging between 10° and 40°, the lower limb positioned at the convexity of the main curve, and LLD of less than 2 cm; individuals requiring bracing or surgical intervention were excluded. Custom sole lifts were used to address the shorter lower limb with the objective of leveling the pelvis. Radiographic evaluations were conducted both before and after intervention using standing full spine posteroanterior radiographs and full leg length radiographs. Statistical analysis was undertaken to evaluate curve correction and its associations with other influencing factors.

Results: The mean structural and functional LLD were 7.1 ± 4.5 mm and 7.1 ± 4.1 mm, respectively. Among the 20 patients, four exhibited structural LLD greater than 10 mm. The average follow-up duration was 6.4 ± 1.9 months (range: 3–8 months). Following sole lift intervention (7.0 ± 3.0 mm), a significant reduction was observed in the TL/L curve compared to the pre-sole lifting measurements (15.6° ± 6.2° vs. 12.1° ± 7.2°, p < 0.001), as well as a notable decrease in the thoracic curve (12.2° ± 4.0° vs. 8.6° ± 6.3°, p = 0.064). Nine patients experienced a significant curve reduction of ≥5°, while eight showed a reduction between 0° and 5°; however, two patients exhibited no change in curve magnitude. Furthermore, the correction rate of the TL/L curve correlated significantly with functional LLD (r = –0.484, p = 0.030) and pelvic obliquity (r = –0.556, p = 0.011), highlighting the active pelvic compensation in maintaining balance between the spine and lower limbs. Conversely, no significant correlation was observed between curve correction and structural LLD (p > 0.05). Additionally, even after adjusting for other influencing factors, the TL/L Cobb angle remained significantly different between pre- and post-sole lifting (p = 0.037).

Conclusion: This study confirmed the effectiveness of sole lift intervention in correcting TL/L and thoracic curves among the mild IS children with a main TL/L curve, providing a supplementary conservative treatment option for patients with the lower limb at the convexity of the main curve. Moreover, our findings underscored the active compensation of the lower limbs and the pelvis in the etiopathogenesis of IS, highlighting the importance of considering their influence in treatment strategies.

Objective: The knee joint of hemophiliacs may face the result of local morphological changes due to long-term irritation of synovitis. This study aims to elucidate the morphological characteristics of distal femur in hemophilic arthritis (HA) and compare the compatibility of three types of prostheses with the anteroposterior (AP) and mediolateral (ML) dimensions of the femoral osteotomy surface.

Methods: This study retrospectively and randomly selected 50 patients with HA registered for treatment at our hospital from June 2016 to August 2022 as the study subjects, with an equal number of male osteoarthritis (OA) patients and healthy male individuals set as the control group. This study used medical digitalization software to simulate osteotomies on the distal femur during total knee arthroplasties (TKA) for 50 patients with HA, OA patients, and the healthy population, respectively, and measure the morphological parameters to compare with three commonly used femoral components of TKA in clinical practice. The differences between the femur resection of anteroposterior and mediolateral (FRAP, FRML) osteotomy surface and the prosthesis’s BOX-AP/ML were compared in three prostheses. One-way ANOVA and multiple Kruskal–Wallis H test were used for the normal or non-normal distribution data, and pairwise comparisons between groups were conducted using the Bonferroni method, and the linear correlation analysis was utilized to assess the relationship between section femoral morphological data and prosthesis parameters.

Result: In HA patients, the morphological characteristics of the distal femur were shown as shorter than femur AP (FAP), medial and lateral condyle anterior–posterior dimension (FMCAP, FLCAP), notch width (NW), posterolateral condyle height (PLCH), posteromedial condyle width (PMCW), and posterior condylar axis length (PCAL) dimension. They had comparatively smaller femur section aspect ratios (p < 0.005). They showed longer posterolateral condyle width (PLCW), anterior condyle mediolateral dimension (FRACML), anterolateral condyle height (ALCH), and femur resection anterior condylar mediolateral (FRACML) dimension (p < 0.005). They showed larger distal femur aspect ratio and resection aspect ratio (FAR, FRAR, p < 0.005). All selected prostheses showed ML undercoverage under similar AP dimensions, and ML undersizing of Attune systems was more obvious in three femoral prostheses.

Conclusion: The distal femur morphological change of HA patient is shown as smaller AP dimension, narrow posterior condyle spacing, lower and shallower trochlear, thinner anterior condyle, wider and lower intercondylar notch and higher posterior-lateral condyle. The selected prostheses showed ML undercoverage under similar AP dimensions. This typical morphological tendency of the distal femur seems to warrant consideration in the process of knee joint prosthesis upgrading.

Objective: Previous cementless total knee arthroplasty (TKA) designs faced challenges with insufficient initial fixation on tibial side, resulting in inferior functional outcomes and survival rates. The Zoned Trabecular Bone Cementless Knee is a novel implant designed for cementless TKA which aims to achieve excellent initial fixation, promoting effective osseointegration. The aim of this research was to compare the early clinical and radiographic results of this cementless TKA with cemented TKA.

Methods: Between September 2021 and April 2022, 64 patients (64 knees) were recruited in this prospective randomized controlled trial to receive either cementless 3D-printed trabecular metal TKA or a cemented posterior stabilized TKA. Preoperative and postoperative clinical evaluations, including the range of motion (ROM), Knee Society Score (KSS), and the Reduced Western Ontario and MacMaster Universities Score (WOMAC), were conducted and analyzed for comparison. Radiographs and computed tomography scans were utilized to assess the initial fixation. The complications between the two groups were also recorded and compared. Continuous data were analyzed for significance using independent-samples t-test or the Mann–Whitney U test and categorical data were analyzed using chi-squared or Fisher’s exact test.

Results: Both groups demonstrated significant enhancement at 12 months follow-up in the ROM compared with baseline (ROM: 94.7 ± 23.4 vs. 113.1 ± 12.3 in cementless group and 96.5 ± 14.7 vs. 111.0 ± 12.8 in cemented group, p < 0.05). However, no statistical differences were observed between the two groups in postoperative ROM, KSS, or WOMAC score. The radiographs and computed tomography scans showed similar results, including radiolucent lines and osteolysis in either femoral or tibial. Additionally, there was no statistical difference in the overall complication rate between the two groups. Notably, one patient in the cementless TKA group required revision for periprosthetic infection as the end point.

Conclusions: This novel 3D-printed trabecular metal cementless TKA achieved comparable clinical outcomes and initial fixation to cemented TKA in early stage. Longer-term examination is necessary to validate these results.

Objective: Diffuse-type tenosynovial giant cell tumors (Dt-TGCTs) commonly occur in the knee joint and tend to recur postoperatively. However, limited clinical data are available on ankle joint involvement especially associated multiportal arthroscopic treatment outcomes. The purpose of this study was to report the clinical results of multiportal arthroscopy-assisted resection of Dt-TGCTs of the ankle.

Methods: We retrospectively reviewed the clinical data of 33 patients with Dt-TGCT of the ankle who underwent multiportal arthroscopic treatment between August 2011 and December 2020. Clinical follow-up included the visual analogue scale (VAS) score, American Orthopedic Foot and Ankle Society (AOFAS) score, Kofoed score, and recurrence rate to assess surgical outcomes. The number of patients who achieved the patient acceptable symptom state (PASS) based on the AOFAS score was also examined. Additionally, the patients were categorized into two groups based on the final surgical approach: Group A who underwent multiportal arthroscopic synovectomy and Group AO who underwent combined arthroscopic and open surgical excision. Intergroup comparisons were conducted. Intraoperative characteristics, such as the number of patients with involvement of the tarsal tunnel and fibularis tendon and the Outerbridge grading of cartilage damage, were recorded to assess the selection of surgical procedures.

Results: Among the 33 patients, 15 were assigned to Group A, and 18 were in Group AO. The median follow-up duration for the 33 patients was 77 months (range, 28–142 months). The median VAS score was 1 (range, 0–4), the AOFAS score was 96 (range, 65–100), and the Kofoed score was 96 (range, 67–100). A total of 27 patients (82%) achieved PASS based on AOFAS scores, while five patients (15%) had recurrence. No statistically significant difference was observed between the two groups in recurrence rate, follow-up VAS score, AOFAS score, Kofoed score, or number of patients who reached the PASS (p > 0.05). In the AO group, 16 cases of Dt-TGCT involved the tarsal tunnel, and 11 cases involved the fibularis tendon. All these patients exhibited extension beyond the joint. In contrast, only one patient in Group A had involvement of the tarsal tunnel. Statistically significant differences were observed between the groups (p < 0.001).

Conclusion: This study demonstrated that, with the assistance of a multiportal arthroscopic approach, surgical excision of Dt-TGCT in the ankle resulted in favorable clinical outcomes with a relatively low recurrence rate. Additionally, patients with extra-articular involvement were more likely to require concomitant open surgery.

Objectives: Cervical spondylosis may lead to changes in the sagittal parameters of the neck and trigger compensatory alterations in systemic sagittal parameters. However, there is currently a dearth of comparative research on the changes and compensatory alterations to sagittal parameters resulting from different types of cervical spondylosis. This study compared the preoperative sagittal alignment sequences among patients with cervical spondylotic radiculopathy (CSR), ossification of the posterior longitudinal ligament (OPLL), and cervical spondylotic myelopathy (CSM) caused by factors resulting from non-OPLL factors.

Materials and Methods: Full length lateral X-ray of the spine and cervical computed tomography (CT) of 256 patients (134 men, 122 women; mean age, 56.9 ± 9.5 years) were analyzed retrospectively. A total of 4096 radiomics features were measured through the lateral X-ray by two spinal surgeons with extensive experience. The clinical symptoms measures were the Japanese Orthopaedic Association (JOA) score, number of hand actions in 10 s, hand-grip strength, visual analog scale (VAS) score. Normally distributed data was compared using one-way analysis of variance (ANOVA) for parametric variables and χ² test were used to analyze the categorical data.

Results: In the OPLL group, the C2-C7 Cobb angle was greater than in the CSR and CSM groups (19.8 ± 10.4°, 13.3 ± 10.3°, and 13.9 ± 9.9°, respectively, p < 0.001). Additionally, the C7-S1 SVA measure was found to be situated in the anterior portion with regards to the CSM and CSR groups (19.7 ± 58.4°, –6.3 ± 34.3° and –26.3 ± 32.9°, p < 0.001). Moreover, the number of individuals with C7-S1 SVA >50 mm was significantly larger than the CSM group (26/69, 11/83, p < 0.001). In the CSR group, the TPA demonstrated smaller values compared to the OPLL group (8.8 ± 8.5°, 12.7 ± 10.2°, p < 0.001). Furthermore, the SSA was comparatively smaller as opposed to both the OPLL and CSM groups (49.6 ± 11.2°, 54.2 ± 10.8° and 54.3 ± 9.3°, p < 0.05).

Conclusion: Patients with OPLL exhibit greater cervical lordosis than those with CSR and CSM. However, OPLL is more likely to result in spinal imbalance when compared to the CSM group. Furthermore, OPLL and CSM patients exhibit anterior trunk inclination and worse global spine sagittal parameters in comparison to CSR patients.

Objective: When implanting the Zero-P device, the screws of Zero-P form a bone wedge with a 40 ± 5° cranial and caudal angle (CCA). However, no study has been performed in the optimal CCA of the Zero-P implant. To investigate whether the cranial/caudal angles (CCA) of the screws affect the clinical and radiological outcomes in patients undergoing ACDF with the Zero-P implant.

Methods: From January 2016 to December 2023, we retrospectively analyzed 186 patients who underwent 1-level ACDF with the Zero-P device. The patients were divided into four groups: group A (cranial angle ≤40°, caudal angle ≤40°); group B (cranial angle ≤40°, caudal angle >40°); group C (cranial angle >40°, caudal angle ≤40°); and group D (cranial angle >40°, caudal angle >40°). The clinical outcomes, including Japanese Orthopaedic Association (JOA), neck disability index (NDI), and visual analogue scale (VAS) scores, the radiological parameters, including cervical lordosis (CL), cervical lordosis of operated segments (OPCL), intervertebral space height (ISH) and fusion rate (FR), and the complications, were evaluated and compared. Parametric tests, non-parametric tests, and chi-square tests were conducted to analyze the data.

Results: The OPCL of group A was significantly less than that of the other groups at the final follow-up (p < 0.05). The ISH of group D was significantly less than that of group A at the final follow-up (p < 0.05). The subsidence rate of group A was significantly less than that of group D at the final follow-up (p < 0.05). At the final follow-up, the upper adjacent-level degeneration (ASD) of group D was significantly less severe than that of groups A and B (p < 0.05). The clinical outcomes do not differ among groups (p > 0.05).

Conclusion: A larger CCA of the screws (cranial angle >40°, caudal angle >40°) was better for maintaining OPCL and reducing the incidence of ASD. A smaller CCA of the screws (cranial angle ≤40°, caudal angle ≤40°) was better for maintaining ISH and reducing the rate of subsidence.

Objective: Posterior condylar offset (PCO) and anterior condylar offset (ACO) exert an influence on the sagittal alignment in total knee arthroplasty (TKA). However, there is no common consensus that the variation range of posterior condylar offset (PCO) is associated with patient-reported outcome measures (PROMs) and the optimum variation range of PCO. This study aims to investigate the correlation between PCO and the PROMs of primary TKA for osteoarthritis (OA) and find out the optimal variation range of the PCO.

Methods: In this study, we performed a radiographic analysis of 106 patients (112 knees) with primary TKA. Patients were divided into two cohorts (A and B) according to the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC). Correlations between the sagittal parameter and WOMAC were investigated using univariate and multivariate analysis. The receiver operating characteristic (ROC) curve was used to establish the cut-off value for the optimal variation range. We then further investigated how different variation range affects the WOMAC subscale score and forgotten-joint-score-12 (FJS-12).

Results: Univariate analysis revealed a correlation between the variation range of PCO (p < 0.01), ACO (p < 0.01) and PROMs. Multivariate analysis showed that only PCO was associated with PROMs. In the ROC graph, the cut-off value of the variation range of PCO is 2.85 mm (AUC = 0.66, Youden index = 0.26). The WOMAC functional ability score of the group outside the PCO variation range of 2.85 mm significantly increased compared to the group within the range.

Conclusion: In this study, PCO variation was significantly associated with clinical outcomes in TKA and the optimal PCO variation range was within 2.85 mm. Maintaining the PCO variation within 2.85 mm could enhance functional recovery and patient satisfaction.

Background: Tourniquet is applied in Total Knee Arthroplasty (TKA) to reduce intraoperative blood loss and improve view of surgical field. However, tourniquet use in TKA is still in dispute. Some researchers find that tourniquet may lead to extra side effects such as aggravated pain and limb swelling, while others consider that tourniquet has no significant adverse impact on clinical outcomes of TKA patients. This trial is conducted to evaluate tourniquet effect on TKA patients.

Methods: A prospective, single-blind, randomized controlled trail is adopted with a sample size of 130 knees from August 2020 to February 2023. Patients undergoing TKA are randomly allocated to tourniquet group and non-tourniquet group. Outcomes including quadriceps thickness and stiffness, operation time, total blood loss, intraoperative blood loss, postoperative blood loss, transfusion rate, thigh circumference, knee and thigh VAS, D-Dimer and CRP level, knee function score, patient satisfaction, and complications are evaluated in this trial. Student’s t-test, Mann–Whitney U test, Pearson’s chi-square test, and Fisher’s exact test are used in this study.

Results: No significant difference in demographic information and baseline outcomes were found (p > 0.05). Participants in the tourniquet group had significantly less total blood loss and intraoperative blood loss, more postoperative blood loss, and higher D-Dimer level on postoperative day 3 when compared with non-tourniquet group (p < 0.05). Other outcomes including quadriceps thickness and stiffness, operation time, postoperative blood loss, transfusion rate, thigh circumference, knee and thigh VAS, D-Dimer level on postoperative day 1, CRP level, knee function score, patient satisfaction, and complications showed no significant difference (p > 0.05).

Conclusion: Tourniquet application can effectively reduce intraoperative blood loss and total blood loss, without significant side effects. Hence, we advocate the regular use of tourniquet in primary TKA.

Objective: Clarifying paraspinal muscle (PM) change in degenerative lumbar scoliosis (DLS) is positive to evaluate the progression of scoliosis. This research compares the characteristic of PM change among different coronal sub-types of DLS and explores its potential clinical significance.

Methods: A total of 84 DLS patients between June 2019 to December 2021 were retrospectively analyzed. Patients were classified into three types based on the coronal balance distance (CBD): Type A, CBD <3 cm; Type B: C7 Plumb Line (C7PL) shifted to the concave side of the curve, and CBD >3 cm; Type C: C7PL shifted to the convex side of the curve, and CBD >3 cm. Fat infiltration rates in the multifidus (MS) and erector spinae (ES) at the apex of the main and fractional curves, and spinopelvic parameters were analyzed statistically. Pearson’s or Spearman’s correlation was applied to analyze the correlation between asymmetric degree of PM change and these parameters in three types.

Results: There were 62 cases with coronal sub-Type A, 6 cases with Type B, and 16 cases with Type C. Patients in Type B and C demonstrated higher fat infiltration in MS on the concave side of both the main and fractional curves when compared to those in Type A. The asymmetric degree of ES change was positively correlated with CBD at the apex of the main curve in Type B and at the apex of the fractional curve in Type C respectively, and that of MS was positively correlated with apical vertebral rotation, while negatively strong-correlated with pelvic incidence and sacral slope in Type C.

Conclusion: PM fatty infiltration presented difference among varied coronal sub-types of DLS patients. The CBD in Type B and C patients was correlated with the asymmetric degree of ES change.

Objective: A robotic system was recently introduced to improve prosthetic alignment during total knee arthroplasty (TKA). The purpose of this multicenter, prospective, randomized controlled trial (RCT) was to determine whether robotic-arm-assisted TKA improves clinical and radiological outcomes when compared to conventional TKA.

Methods: One hundred and thirty patients who underwent primary TKA were enrolled in this prospective, randomized controlled trial, which was conducted at three hospitals. Five patients were lost to follow-up 6 weeks after surgery. Therefore, 125 participants (63 in the intervention group and 62 in the control group) remained in the final analysis. The primary outcome was the rate at which the mechanical axis of the femur deviated by less than 3° from the mechanical axis of the tibia. This was evaluated by full-length weight-bearing X-rays of the lower limb 6 weeks postoperatively. Secondary outcomes included operation times, 6-week postoperative functional outcomes evaluated by the American Knee Society score (KSS) and the Western Ontario and McMaster Universities osteoarthritis index (WOMAC), short form-36 (SF-36) health survey results, and the occurrence of adverse events (AEs) and serious adverse events (SAEs).

Results: At 6 weeks postoperatively, we found that the rate of radiographic inliers was significantly higher in the intervention group (78.7% vs 51.6%; p = 0.00; 95% confidence interval, 10.9% to 43.2%). The operation was significantly longer in the intervention group than in the control group (119.5 vs 85.0 min; p = 0.00). There were no significant differences in the 6-week postoperative functional outcomes, SF-36, AEs, and SAEs between the two groups. There were no AEs or SAEs that were determined to be “positively related” to the robotic system.

Conclusion: Robotic-arm-assisted TKA is safe and effective, as demonstrated in this trial.

Objective: The craniovertebral junction (CVJ) presents intricate anatomical challenges. In severe or irreducible malformations, complications such as reduction loss and fixation failure may occur, necessitating revision surgery. The posterior facet joint distraction and fusion (PFDF) technique, offers a solely posterior approach for revisions. Hence, we delineate varied revision scenarios, proposing surgical strategies and technical details to enhance outcomes and mitigate risks, thereby enriching the neurosurgical community’s repertoire.

Methods: This was a retrospective cohort study, analyzed patient data from Xuanwu Hospital, between 2017 to 2023. All patients had a history of surgical treatment for CVJ malformations, and experienced failure or loss of reduction. The distance from the odontoid process tip to the Chamberlain’s line (DCL), the atlantodental interval (ADI), clivus-canal angle, cervicomedullary angle, width of subarachnoid space, CVJ area, and width of syrinx were used for radiographic assessment. Japanese Orthopaedic Association (JOA) scores and SF-12 scores were used for clinical assessment. Independent sample t-tests were employed. A significance level of p < 0.05 indicates statistically significant differences.

Results: We analyzed data from 35 patients. For patients who underwent PFDF, the postoperative DCL, ADI, and clivus-canal angle significantly improved. For all patients, the postoperative cervicomedullary angle, width of subarachnoid space, CVJ area, and width of syrinx all demonstrated significant improvement, indicating the relief of neural compression. All patients showed significant improvement in both symptoms and clinical assessments.

Conclusion: Severe atlantoaxial joint locking or ligament contracting are the fundamental cause of reduction and fixation failure. Anterior odontoidectomy is indicated for patients with robust bony fusion of the atlantoaxial joint in an unreduced position. The PFDF technique is safe and effective for patients with incomplete atlantoaxial bony fusion. Preoperative assessment of surgical feasibility and vertebral artery status ensures surgical safety and efficacy.

Objective: To retrospectively evaluate clinical outcomes, including function and pain, of patients after our all arthroscopic “whole layer” rotator cuff repair technique with simultaneous biceps tenodesis procedure; factors influencing results were also evaluated. Given the frequent association of rotator cuff tear with long head of biceps lesion and the need for effective combined treatment strategies, this study aims to evaluate the efficacy of our technique and compare it with established methods. We hypothesized that our technique would significantly improve function and reduce pain in patients with rotator cuff tears and biceps pathology.

Methods: This is a retrospective study that included patients older than 20 years who underwent all arthroscopic “whole layer” rotator cuff repair technique with simultaneous biceps tenodesis procedures for concomitant rotator cuff tear and long head biceps pathology, from 2016 to 2020. Patients were evaluated preoperatively and at a minimum of 2 years of follow-up using the American Shoulder and Elbow Surgeons (ASES) and visual analogue scale (VAS) scores paired t-tests were used for analysis and statistical significance was set at p < 0.05(two-tailed). The satisfaction rate and complications were also evaluated.

Results: After an average follow-up of 2.3 years, 118 patients demonstrated significant improvement in both the ASES score (from 36.13 to 95.01, p < 0.001) and VAS score (from 6.81 to 0.89, p < 0.001). Ninety-four percent of the patients reported satisfaction with the surgical outcome. No complications related to Popeye deformity, biceps cramping pain, or ipsilateral shoulder reoperation were observed. Factors such as age, sex, body mass index (BMI), smoking status, alcohol consumption, hypertension, and diabetes did not influence the results. Patients showed significant improvement in both the ASES and VAS scores (p < 0.001).

Conclusion: At a mean follow-up time of 2.3 years, the all arthroscopic “whole layer” rotator cuff repair technique with simultaneous biceps tenodesis is a therapeutic and efficient procedure. The procedure revealed a satisfactory functional outcome, reduced pain, and minimal complications and reoperations.

Objective: The prognostic nutritional index (PNI) has been reported as a significant predictor in various diseases. However, the prognostic value of the PNI in geriatric hip fracture patients has not been thoroughly evaluated. This study aimed to investigate the association between admission PNI and 3-year mortality in those patients.

Methods: In this post hoc analysis, we included patients aged ≥65 years who underwent surgery for hip fracture between 2018 and 2019. The admission PNI was calculated as serum albumin (g/L) +5 × total lymphocyte count (×10⁹/L). Patients were categorized into four groups based on PNI quartiles (≤ 43.55, 43.55–46.55, 46.55–49.20, and >49.20, respectively). The median follow-up duration was 3.1 years. Cox proportional hazards models were used to calculate the hazard ratio (HR). Receiver operating characteristic curve (ROC) was conducted for using PNI to predict mortality.

Results: Of the 942 eligible patients, 190 (20.2%) patients died during the follow-up. Compared to patients in the first quartile (Q1), those in the second (Q2), third (Q3), and fourth (Q4) quartiles had significantly lower mortality risks (HRs 0.50, 95% CI 0.35–0.74; 0.41, 95% CI 0.26–0.64; and 0.26, 95% CI 0.15–0.45, respectively). The optimal cutoff of PNI for predicting mortality was set as 45.275 (sensitivity, 0.674; specificity, 0.692; area under the curve (AUC), 0.727). Patients with higher PNI (>45.275) had a significant lower mortality risk (HR 0.39, 95% CI 0.28–0.55) compared to those with lower PNI (≤ 45.275).

Conclusion: PNI is a reliable and independent predictor of 3-year mortality after hip fracture surgery in the elderly.

Objective: The cortical bone trajectory (CBT) technology is an effective substitute for traditional pedicle screw (PS) technology. However, there is still controversy about the CBT screw technology placement strategy. The objective of this study was to simulate cortical screw placement with the help of three-dimensional (3D) software, to discuss the differences in screws between genders and vertebral segments, and to explore a safer and more efficient strategy for cortical screw placement.

Methods: Mimics Medical software was used to construct a 3D model of the lumbar spine, and the placement of CBT screws was simulated. The volume of each vertebral body from L1 to L5, the pedicle isthmus height (IH), the pedicle isthmus width (IW), and the sagittal vertebral distance (SAVD) were measured. The transverse distance (TD) and the longitudinal distance (LD) between the ideal starting point (SP) and the clinical SP (the intersection Q of the midline of the superior articular process and the horizontal line 1 mm below the transverse process) were measured. The cephalad angle (CA), lateral angle (LA), maximum screw diameter (MSD), maximum screw length (MSL) of each trajectory of the L1 to L5 vertebral bodies, and the percentage of the screw insertion depth (PSID) into the vertebral body were measured. Data were statistically analyzed using Student’s t-test, one-way analysis of variance (ANOVA), and Tukey’s test.

Results: Vertebral anatomical parameters and CBT screw parameters differed between males and females. Female patients had lower IH, IW, SAVD, CA, LA, MSD, and MSL than males. IH was greatest in L1 (male, 17.81 mm; female, 16.12 mm) and the smallest in L5 (male, 14.11 mm; female, 13.05 mm). IW was smallest in L1 (male, 8.89 mm; female, 7.37 mm) and greatest in L5 (male, 16.59 mm; female, 15.43 mm). The MSD of males was smallest in L1 (6.05 mm) and greatest in L3 (7.06 mm); the MSD of females was smallest in L1 (5.13 mm) and greatest in L4 (6.64 mm). MSL was greatest at L3 (male, 33.63 mm; female, 32.28 mm) and smallest at L5 (male, 31.25 mm; female, 29.97 mm). CA was smallest in L1 (male, 22.80°; female, 21.92°) and greatest in L3 (male, 25.29°; female, 24.33°). LA was smallest in L1 (male 12.37°, female 11.27°) and greatest in L5 (male 13.56°, female 12.96°). Among the males, TD was smallest at L1 (–0.51 mm) and greatest at L5 (1.37 mm), while LD was greatest at L2 (3.46 mm) and smallest at L5 (2.40 mm). In females, TD was greatest at L1 (0.12 mm) and smallest at L3 (–0.51 mm), while LD was greatest at L1 (3.69 mm) and smallest at L5 (2.08 mm). In the overall sample, the incidence of SAVD and PSID gradually increased from L1 to L5.

Conclusion: The optimal screw placement strategy for CBT screws varies significantly according to sex and vertebral body segments, particularly noting the specificity of screw placement at L5. The optimal screw placement strategy should be selected based on the patient’s sex and segment characteristics before surgery to maximize the safety and accuracy of CBT screw placement.

Study Design: Retrospective clinical study.

Objective: The purpose of this study was to establish a novel classification of migrated lumbar disk herniation (LDH) based on magnetic resonance imaging and provide appropriate treatment strategies for each type through algorithms.

Summary of Background Data: Full-endoscopic lumbar discectomy is a surgical technique that has been developed rapidly in recent years. For migrated LDH, few surgeons currently classify it with multiplanar positioning, and there is no consensus on the choice of treatment strategy. Therefore, we established a new multiplanar classification criteria that can localize the lesions more accurately than previous studies.

Methods: A total of 263 eligible patients from March 2017 to March 2022 were included. Protrusions for each patient were located based on our classification and the surgical approach was selected according to our algorithms. The clinical symptoms of all patients before surgery, and at 1 day, 1 month, 3 months, 6 months, and 12 months after surgery were collected. Evaluations were performed using visual analogue scale (VAS), Oswestry Disability Index (ODI) and modified MacNab criteria. We used the chi-squared test, one-way analysis of variance (ANOVA), and t-test to compare perioperative results and postoperative 3-month, 6-month, and 12-month follow-up results.

Results: VAS (low back pain) scores were reduced from 5.33 ± 2.67 to 0.73 ± 0.77 (p < 0.001), and VAS (leg pain) scores were reduced from 7.44 ± 2.21 to 0.37 ± 0.51 (p < 0.001). ODI scores improved from 58.46 ± 8.04 to 12.57 ± 2.51 (p < 0.001). According to the modified MacNab criteria, the excellent and good rate reached 92.78% at the 12-month follow-up. Twenty-six patients developed complications, all of which improved after treatment. Recurrence occurred in 13 patients, and four of them underwent secondary surgery.

Conclusions: This is an innovative classification method using multi-plane positioning, and the algorithm used with it can help surgeons make appropriate choices when using endoscopic technology to treat migrated LDH. Statistical analysis of follow-up data confirmed that this is a safe and effective strategy.

Objectives: Due to the technical challenges associated with femoral reconstruction in total hip arthroplasty for patients with developmental dysplasia of the hip (DDH), the exact indications for using femoral modular stems, despite their satisfactory clinical outcomes, remain poorly investigated. This study sought to assess the morphology of the femur and acetabulum, and to investigate the discriminative ability of femoral anteversion (FA), acetabular anteversion (AA), and combined anteversion (CA) on the selection of femoral modular stem in dysplastic hips.

Methods: Retrospective data were collected from multiple centers on a total of 230 cases who underwent THA due to DDH from January 1, 2020, to March 1, 2023. There were 46 males and 184 females, with an average age of 51.57 ± 14.87. Patients were stratified according to Crowe and Eftekhar classifications. FA, AA, and CA were measured using computed tomography (CT). The distribution of these indices in different grades of dysplastic hips was compared, and the correlation between these indices and the selection of femoral modular stem was analyzed. Receiver operating characteristic (ROC) and likelihood statistics were performed to investigate the discriminating and predictive value of each index in selecting modular stem.

Results: Two hundred and thirty hips were included in the study. FA increased as the subluxation percentage increased: type I, 21.5°; type II, 28.6°; type III, 34.9°; and type IV, 39.7°. AA was smaller in type I (16.9°) and higher in types II, III, and IV (18.9–22.6°). The area under the curve for the modular stem was 0.87 for FA, 0.86 for CA, and 0.65 for AA. The optimal cutoff values were FA > 32.6°, CA > 50.7°, and AA > 23.3°.

Conclusion: Excessive AA and femoral anteversion FA were observed in Crowe types II, III, and IV cases. FA and CA demonstrated strong discriminative ability and predictive value in the selection of a modular stem. The best cutoff values were ≥32.6° for FA and ≥50.7° for CA in discriminating the use of modular stem. Surgeons may contemplate the use of a modular stem when the preoperative evaluation approaches the cutoff value.

Objective: Osteoporosis is a severe bone disease with a complex pathogenesis involving various immune processes. With the in-depth understanding of bone immune mechanisms, discovering new therapeutic targets is crucial for the prevention and treatment of osteoporosis. This study aims to explore novel bone immune markers related to osteoporosis based on single-cell and transcriptome data, utilizing bioinformatics and machine learning methods, in order to provide novel strategies for the diagnosis and treatment of the disease.

Methods: Single cell and transcriptome data sets were acquired from Gene Expression Omnibus (GEO). The data was then subjected to cell communication analysis, pseudotime analysis, and high dimensional WGCNA (hdWGCNA) analysis to identify key immune cell subpopulations and module genes. Subsequently, ConsensusClusterPlus analysis was performed on the key module genes to identify different diseased subgroups in the osteoporosis (OP) training set samples. The immune characteristics between subgroups were evaluated using Cibersort, EPIC, and MCP counter algorithms. OP’s hub genes were screened using 10 machine learning algorithms and 113 algorithm combinations. The relationship between hub genes and immunity and pathways was established by evaluating the immune and pathway scores of the training set samples through the ESTIMATE, MCP-counter, and ssGSEA algorithms. Real-time fluorescence quantitative PCR (RT-qPCR) testing was conducted on serum samples collected from osteoporosis patients and healthy adults.

Results: In OP samples, the proportions of bone marrow-derived mesenchymal stem cells (BM-MSCs) and neutrophils increased significantly by 6.73% (from 24.01% to 30.74%) and 6.36% (from 26.82% to 33.18%), respectively. We found 16 intersection genes and four hub genes (DND1, HIRA, SH3GLB2, and F7). RT-qPCR results showed reduced expression levels of DND1, HIRA, and SH3GLB2 in clinical blood samples of OP patients. Moreover, the four hub genes showed positive correlations with neutrophils (0.65–0.90), immature B cells (0.76–0.92), and endothelial cells (0.79–0.87), while showing negative correlations with myeloid-derived suppressor cells (negative 0.54–0.73), T follicular helper cells (negative 0.71–0.86), and natural killer T cells (negative 0.75–0.85).

Conclusion: Neutrophils play a crucial role in the occurrence and development of osteoporosis. The four hub genes potentially inhibit metabolic activities and trigger inflammation by interacting with other immune cells, thereby significantly contributing to the onset and diagnosis of OP.

Background: Although the specific relationship between the stress changes in the external fixator during tibial fracture treatment and the bone healing process remains unclear, it is believed that stress variations in the external fixator scaffold can, to a certain extent, reflect the progress of tibial healing.

Objective: This study aims to propose a non-invasive method for assessing the degree of fracture healing by monitoring the changes in stress transmission, the locations of stress-sensitive points, and displacement in the external fixator-tibia system during the healing process of tibial fractures.

Methods: In this study, finite element models of tibial fractures at various healing stages were developed. Physiological conditions, including axial, torsional, and bending loads on the tibia, were simulated to evaluate stress and strain within the external scaffold-tibia system under normal physiological loading conditions.

Results: The results indicate variations in the stress distribution between the external fixator and the tibia during different stages of healing. In the early phase of fracture healing, the external fixator plays a crucial role as the primary load-bearing unit under all three loading conditions. As the fracture healing progresses, the stress on the tibia gradually increases, concentrating on the medial part of the tibia under axial and torsional loading, and at the upper and lower ends, as well as the central part of the anterior and posterior tibia during bending loading. The stress at the callus gradually increases, while micro-movements decrease. The stress within the external bracket gradually decreases, with a tendency for the connecting rod to transfer stress towards the screws. Throughout the fracture healing process, the location of maximum stress in the external fixator remains unchanged. Under axial and torsional loading, the maximum stress is located at the intersection of the lowest screw and the bone cortex, while under bending loading, it is at the intersection of the second screw and the connecting rod.

Conclusion: During the bone healing process, stress is transferred between the external fixation frame and the bone. As bone healing advances, the stress on the connecting rods and screws of the external fixation frame decreases, and the amplitude of stress changes diminishes. When complete and robust fusion is achieved, stress variations stabilize, and the location of maximum stress on the external fixation frame remains unchanged. The intersections of the lowest screw and the bone cortex, as well as the second screw and the connecting rod, can serve as sensitive points for monitoring the degree of bone healing.

Objective: Air pollution is increasing and threatening human health. The objective of this study is to investigate the population distribution characteristics of elderly osteoporosis fractures in Hebei Province and Xinjiang Uygur Autonomous Region and to analyze the effects of air pollutants on the number of elderly osteoporosis fracture inpatients in the two regions.

Method: A retrospective collection of elderly osteoporosis fracture cases was conducted in selected hospitals in Hebei Province and Xinjiang Uygur Autonomous Region from January 1, 2018 to December 31, 2022. The chi-square test was used to compare the distributional characteristics of the population in the two regions. Additionally, we used a distributed lag nonlinear model (DLNM) in order to assess the effect of air pollutants on the number of daily hospital admissions of elderly osteoporosis fracture patients in different regions.

Result: A total of 19,203 elderly osteoporosis fracture patients were included in the study. The average age of these patients was 76.66 ± 7.55 years, and the majority of them were female (13,514 instances, 70.37%). The disparities in age distribution (χ² = 133.9 p < 0.001), fracture site (χ² = 62.0 p < 0.001), and hospitalization cost (Z = –15.635 p < 0.001) between the two regions were statistically significant. The lag effect curves of PM2.5, PM10, and NO₂ on the number of elderly osteoporosis fracture hospitalizations in Xinjiang Uygur Autonomous Region exhibited a similar pattern resembling a “W”-shaped curve. All three pollutants reached their highest values after a lag time of 14 days (PM2.5: RR = 1.053, 95% CI: 1.031, 1.074; PM10: RR = 1.031, 95% CI: 1.018, 1.043; NO₂: RR = 1.125, 95% CI: 1.070, 1.182). In Hebei Province, the largest impacts of PM2.5 and PM10 were observed after a lag of 14 days (PM2.5: RR = 1.022, 95% CI: 1.013, 1.028; PM10: RR = 1.013, 95% CI: 1.008, 1.018). Similarly, the maximum effect of NO₂ was observed after a lag of 11 days (RR = 1.020, 95% CI: 1.010, 1.028).

Conclusion: There were differences in the epidemiological characteristics of hospitalized patients with osteoporosis fractures between the two regions, PM2.5, PM10, and NO₂ increased the number of hospitalizations for osteoporosis fractures. Exposure to air pollutants such as PM2.5 increases the risk of osteoporosis fractures in the elderly population.

The upper cervical spine has a complex anatomical structure, making anterior surgical approaches challenging and prone to complications. This study aims to explore the use of bilateral submandibular incisions to provide safer and more convenient exposure of the upper cervical spine and to assess the feasibility of this approach for anterior surgical treatment of complex upper cervical diseases. From November 2019 to August 2021, three patients with malignant tumors of the upper cervical spine were subjected to an anterior–posterior combined approach for cervical tumor resection. The cohort consisted of one male and two females, aged between 41 and 51 years. The anterior approach began with a submandibular incision, followed by blunt dissection through the prevertebral muscles to expose the diseased vertebra. Subsequently, the diseased vertebra was excised, and either a titanium cage or a pre-customized 3D-printed artificial vertebral body was implanted anteriorly. Then, posterior fixation of the cervical spine was performed using pedicle screws to provide additional stability. Follow-up ranged from 8 to 34 months. All patients experienced varying degrees of pain relief within 24 hours post-operation. Frankel grading showed improvement by at least one grade in all three cases. Regular X-ray and magnetic resonance imaging examinations revealed no tumor recurrence or involvement of adjacent vertebrae in the surgical area. The anterior bilateral submandibular horizontal incision approach offers comprehensive exposure of the anatomical structures of the upper cervical spine. This approach introduces a new option for the anterior treatment of upper cervical spine diseases.

This study aimed to investigate the application of the cup-on-cup technique in revision total hip arthroplasty (THA) and report clinical and radiographic outcomes from a series of case follow-ups. Retrospective analysis of 10 patients who underwent acetabular prosthesis revision with cup-on-cup technique. According to the Paprosky classification of acetabular bone defects, there were 2 cases of type II C, 3 cases of type III A, and 5 cases of type III B. The average follow-up was 54.8 ± 5.1 months, and the Harris score of the hip joint increased from 37.0 ± 9.9 preoperatively to 80.5 ± 3.1 postoperatively at the final follow-up (p < 0.001). Comparing the surgical side’s hip center of rotation (COR) to the contralateral side, the preoperative average upward displacement was 33.8 ± 15.0 mm, while the postoperative average upward displacement was 0.2 ± 3.3 mm (p < 0.001). Similarly, the preoperative average inward displacement was 9.1 ± 5.1 mm, while the postoperative average outward displacement was 1.8 ± 1.6 mm (p < 0.001). There was no significant difference (p = 0.71) between the average density values of the contralateral and surgical sides at the final follow-up, which were 127.4 ± 13.7 and 125.0 ± 14.8, respectively. During the follow-up period, all patients achieved satisfactory radiographic outcomes, and no prosthetic loosening was observed. The cup-on-cup technique can reconstruct acetabular bone defects and restore hip COR in revision THA, with favorable clinical and radiographic outcomes.

Arthroscopic treatments of hip synovial osteochondromatosis are mostly performed under traction, resulting in neurovascular injury or iatrogenic damage to the labrum or cartilage. This study aimed to assess the effectiveness of outside-in hip arthroscopy without traction in treating hip synovial osteochondromatosis. This retrospective study was conducted on a series of patients with hip synovial osteochondromatosis treated using outside-in hip arthroscopy without traction in our hospital between 2018 and 2020. Plain radiography and magnetic resonance imaging (MRI) scans were obtained. The Harris hip score (HHS), hip range of motion (ROM), and visual analog scale (VAS) scores were analyzed. The preoperative scores and last follow-up scores were compared with a paired-sample t test. The complications and recurrence postsurgery were recorded. This study included five patients (three male and two female) with an average age of 41 years (range 28–54 years). The mean follow-up time was 25.2 months (range 18–36 months). All patients experienced groin pain relief and improved ROM. The mean VAS score was significantly lower postoperatively (0.4 ± 0.5) than preoperatively (3.2 ± 0.8) (p < 0.001). The mean HHS improved from 58.6 ± 12.7 (range 43–73) to 89.8 ± 5.26 (range 81–95) (p < 0.001). No major complications, including infection, perineal numbness and swelling, neurotrosis, thromboembolism, or severe persistent pain, were reported. Synovial osteochondromatosis recurred in one patient after 2 years of follow-up without any obvious symptoms such as hip pain or joint locking. Therefore, no further treatment was necessary. This study showed that outside-in hip arthroscopy without traction might be a viable option for treating hip synovial osteochondromatosis, effectively and safely relieving symptoms with minimal complications, especially in patients without lesions in the central compartment.

Background: Strokes in young individuals often stem from unusual causes. Posterior circulation ischemic stroke caused by vertebral artery insufficiency due to atlantoaxial instability or dislocation is rare. We present a case of posterior circulation ischemic stroke due to an unstable os odontoideum and review the current literature. The clinical features and imaging manifestations are described to promote awareness of etiology, early diagnosis, and assessment.

Case Presentation: A 24-year-old male presented with recurrent right-sided limb numbness and weakness and cerebellar ataxia due to posterior circulation ischemic stroke. The work-up revealed thrombosis reformation in the tortuous left vertebral artery. It is noteworthy that the patient developed compression and chronic damage of the vertebral artery secondary to atlantoaxial instability and lateral dislocation due to an os odontoideum. He underwent antiplatelet and anticoagulant therapy, cervical traction, and posterior atlantoaxial screw fixation and fusion with iliac crest autograft. The postoperative course was uneventful. At 6-month follow-up, the patient had a solid fusion mass and rigid stability of the atlantoaxial joint without neurologic deficits or ischemic sequelae.

Conclusions: For unexplained posterior circulation ischemic stroke, it is important to consider unstable os odontoideum as a potential etiology, especially in pediatric and young adult male patients. Atlantoaxial instability and dislocation with os odontoideum, especially when occurring laterally, may cause insufficiency of the vertebral artery and subsequent posterior circulation ischemic strokes. The significance of lateral atlantoaxial dislocation in the genesis of vertebral artery injury and the necessity for specific positional imaging are emphasized.