Orthopaedic Surgery最新文献

Background: Anterior controllable antedisplacement and fusion (ACAF) is an emerging surgical approach for treating cervical ossification of the posterior longitudinal ligament (C-OPLL), yet there is limited data on its long-term efficacy and safety. The present study aimed to analyze the short- and long-term postoperative clinical and radiological outcomes and perioperative complications of ACAF for patients with C-OPLL.

Methods: This was a single-center, retrospective, cohort study, with the mean duration of follow-up of at least 24 months. A total of 111 patients with C-OPLL in our institution from June 2017 to June 2019 were assessed preoperatively and at 3 days, 3, 6, 12, and 24 months postoperatively. The primary outcome was the recovery of neurological function, measured with the Japanese Orthopedic Association (JOA) score. The secondary outcomes included pain, Cobb angle, spinal canal invasion rate, and surgery-related complications.

Results: The postoperative JOA score at each follow-up was significantly better than the preoperative JOA score, regardless of preoperative spinal canal invasion rate, K-line, and segment length. The visual analog scale (VAS) score also decreased dramatically 3 days after surgery and was maintained at a low level throughout the follow-up period. Improvements in Cobb angle and invasion rate were observed right after the operation and were maintained for 2 years thereafter.

Conclusions: ACAF could achieve satisfactory recovery of neurological function in C-OPLL patients during a follow-up of 24 months, regardless of preoperative spinal canal invasion rate, preoperative K-line, or surgical segment length.

Objective: The relationship between cervical disc degeneration and bone quality of adjacent vertebral body remains controversial. This study aims to investigate the relationship between cervical disc degeneration and bone quality of the adjacent vertebral body and sub-endplate bone with a new MRI-based bone quality score in patients over 50 years with cervical spondylosis.

Methods: We retrospectively reviewed 479 cervical disc segments from 131 patients. Disc degeneration at levels C3/C4-C6/C7 was graded using T2-weighted MRI. Vertebral body quality (VBQ) score and sub-endplate bone quality (EBQ) score from C3 to C7 were computed from T1-weighted MRI images. Additionally, bone mineral density (BMD) of the cervical vertebrae was measured in 52 patients using a novel phantom-less quantitative computed tomography (PL-QCT) system. The correlation between bone quality score and Pfirrmann grade was analyzed and risk factors for VBQ and EBQ were further evaluated.

Results: Significant differences were found in cranial VBQ among different Pfirrmann grades, with a score of 2.55 ± 0.54 for Grade 5 discs, which was lower compared to Grades 4 (2.70 ± 0.56) (p < 0.05) and 3 (2.81 ± 0.58) (p < 0.01). Caudal VBQ for Grade 5 discs (2.43 ± 0.52) was also significantly lower than for Grade 3 discs (2.66 ± 0.54) (p < 0.01). EBQ scores decreased with increasing Pfirrmann grades. Negative correlations were observed between both cranial and caudal VBQ and EBQ scores and Pfirrmann grades. Grades 4 and 5 discs were identified as independent risk factors for decreased caudal VBQ and EBQ, whereas only Grade 5 was a significant risk factor for decreased cranial EBQ. Additionally, a moderate correlation (0.4 < R < 0.6, p < 0.05) was noted between vertebral body BMD and VBQ at each cervical level.

Conclusion: In individuals over 50 years with cervical spondylosis, the severity of disc degeneration was closely correlated with denser bone quality in both the caudal vertebral body and sub-endplate, as measured by VBQ and EBQ scores. These findings suggest that worsening disc degeneration is associated with increased bone density in specific areas of the cervical spine.

Objective: Osteoporosis is a crucial risk factor for screw loosening. Our studies indicate that the bone mineral density (BMD) in the screw trajectory is a better predictor of screw loosening than the BMD of the lumbar spine or the screw insertion position. Research has shown that anchorage on the screw tip is the most significant factor for screw anchorage ability, while others argue that decreased bony quality in the pedicle poses a significant risk for screw loosening. This study aimed to determine whether the bony quality of the screw tip, pedicle, or screw-anchored vertebral body plays the most significant role in screw anchorage ability.

Methods: A total of 73 patients who underwent single-segment bilateral pedicle screw fixation, along with posterior and transforaminal lumbar interbody fusion (PLIF and TLIF), from March 2019 to September 2020 were included in this retrospective study. The Hounsfield unit (HU) value of the fixed vertebral bodies, the entire screw trajectory, screw tip, screw-anchoraged vertebral body, and pedicles were measured separately. Data from patients with and without screw loosening were compared, and regression analyses were conducted to identify independent risk factors. Additionally, the area under the curve (AUC) values were computed to assess the predictive performance of different parameters. Furthermore, fixation strength was calculated in numerical models with varying bony densities in different regions.

Results: HU values were found to be significantly lower in the loosening group across most measuring methods (HU values in the pedicle, 148.79 ± 97.04, 33.06 ± 34.82, p < 0.001). Specifically, the AUC of screw loosening prediction was notably higher when using HU values of the pedicle compared to other methods (AUC in the pedicle > 0.9 and in the screw insertion position > 0.7). Additionally, computational results for fixation strength revealed a clear decline in screw anchorage ability in models with poor BMD in the pedicle region.

Conclusions: Pedicle bone quality plays a more significant role in screw anchorage ability than that in other regions. The innovation of bony augmentation strategies should pay more attention to this region to optimize the screw anchorage ability effectively.

Anterior cruciate ligament (ACL) injuries are the most common knee joint injuries related to sports activities in clinical practice. For treating ACL injuries, anatomical reconstruction surgery is often the preferred method. The over-the-top (OTT) technique is a surgical approach that eliminates the need for creating a femoral tunnel. According to the existing literature, the OTT technique offers distinct advantages, particularly for skeletally immature individuals and in revision cases. Currently, femoral tunnel failure is the most common cause of ACL reconstruction failure, which can lead to less than optimal postoperative performance of the ACL and a higher likelihood of needing a revision. Additionally, mistakes in the placement of the femoral tunnel and the subsequent risk of tunnel enlargement can increase the complexity of revision procedures, ultimately reducing the long-term clinical effectiveness for patients. In contrast, the OTT technique has shown excellent biomechanical performance, avoids the need for bone tunnels, is economically practical, and has been proven to provide satisfactory therapeutic outcomes both in the short and long term, especially for skeletally immature individuals and in revision cases. The OTT technique is deemed a safe and effective surgical method for treating ACL injuries. In summary, the OTT technique has unique benefits for skeletally immature individuals and in revision cases, making it a viable option worth considering. Level of evidence V.

Objectives: Currently, unilateral biportal endoscopic (UBE) and uniportal full-endoscopic (UFE) techniques for the treatment of lumbar disc herniation (LDH) are gaining popularity. However, studies investigating the number of surgeries needed for surgeons to achieve proficiency in these procedures are lacking. This study aims to compare the early learning curve for UBE and UFE when treating LDH.

Methods: The learning curve for two fellowship-trained surgeons at our institution was retrospectively assessed for 160 consecutive patients (UFE: n = 100, UBE: n = 60) who underwent procedures between September 2020 and May 2023. Surgeon 1 first learned UBE, followed by UFE (S1BF), while Surgeon 2 first learned UFE and then UBE (S2FB). Operation time was evaluated as the primary outcome for determining the learning curve using cumulative sum (CUSUM) analysis. Secondary outcomes assessing endoscopic prowess include surgical outcomes, such as fluoroscopy usage times, postoperative hospital stays, the incidence of complications, and clinical outcomes, including visual analog scale (VAS) scores for back and leg pain, Oswestry disability index (ODI) score and modified MacNab criteria.

Results: The learning curve analysis identified the cutoff point in UBE at 14 cases and 11 cases for S1BF and S2FB, respectively, and in UFE at 31 cases and 27 cases, respectively. Without UFE or UBE experience, at the last follow-up, both the VAS back and leg pain in UFE were significantly higher than that in UBE (p < 0.05). Furthermore, the incidence of complications of UFE was also higher than that of UBE (29.0% vs. 7.1%). When surgeons have previous UFE or UBE experience, there was no significant difference in the clinical outcomes between UFE and UBE, and the complication rates were also similar (p > 0.05). After gaining UBE experience, the UFE performed by S1BF showed significantly better outcomes in fluoroscopy usage times (p = 0.024), surgical complications (p = 0.036), last follow-up VAS back pain (p = 0.003), and leg pain (p < 0.001) compared to S2FB. However, after gaining UFE experience, the S2FB only showed significant improvement in operation time (p = 0.041) during the process of learning UBE compared to S1BF.

Conclusions: Regardless of whether UBE or UFE is learned first, both techniques can significantly shorten the learning curve for the other technique. We recommend prioritizing the learning of UBE. Compared with UBE, the learning curve for UFE was significantly steeper and longer with higher incidence of complications in the early stage.

Background: Postoperative spinal epidural hematoma (SEH) is a rare but serious complication following lumbar surgery, with cauda equina syndrome (CES) being one of its most devastating outcomes. While CES typically presents with a combination of bladder and/or bowel dysfunction, diminished sensation in the saddle area, and motor or sensory changes in the lower limbs, atypical cases with isolated urinary symptoms are less recognized and pose significant diagnostic challenges.

Case presentation: We report the case of a 46-year-old male who developed CES following lumbar microdiscectomy, presenting solely with urinary retention, without the classic signs of lower limb weakness or perineal sensory loss. Initial symptoms were attributed to postoperative urinary issues, delaying the diagnosis of CES. On postoperative day 7, magnetic resonance imaging (MRI) revealed SEH, and emergency hematoma evacuation was performed. Despite the delayed intervention, the patient made a full neurological recovery, with bladder and bowel functions restored by 3 months postoperatively.

Conclusion: This case highlights the importance of recognizing CES in patients with isolated urinary dysfunction after lumbar surgery, even when typical neurological symptoms such as lower limb weakness or perineal sensory loss are absent. Early detection and prompt surgical intervention are critical, as delayed diagnosis may result in permanent neurological deficits. Moreover, this case underscores the need for vigilant postoperative monitoring, especially of urinary function, as isolated urinary symptoms may signal early CES. Maintaining a high index of suspicion for CES, even in atypical presentations, can facilitate timely diagnosis and improve patient outcomes. Furthermore, this case highlights the need for continued research into the prevention of SEH and the development of more robust diagnostic criteria for CES in postoperative patients. Future studies should focus on developing more comprehensive guidelines for monitoring postoperative patients, especially regarding urinary function, to aid in the early detection of CES.

Objective: Whether first coronal reverse vertebrae (FCRV) can directly cause biomechanical changes in adjacent segments remains unclear. The objective of this study was to explore the biomechanical changes in adjacent discs of the FCRV to better understand the stress distribution of adolescent idiopathic scoliosis (AIS).

Methods: According to the plain CT scan data of T8-T10 segment of an AIS patient, T9 was the FCRV, and a three-dimensional FE model was established accurately. The T8-T9 segment disc was defined as the adjacent upper disc (UD), axial section as half of the upper disc (HUD). Similarly, T9-T10 segment disc was the adjacent lower disc (LD), axial section as half of the lower disc (HLD). The biomechanical changes in adjacent discs of the FCRV under different loads were assessed.

Results: The maximum Von-Mises stress values of the LD were greater under various loads than those of the HLD, UD, and HUD. The average stress on the LD was greater than that of the other discs under the left lateral bending (LLB) or right lateral bending (RLB) load. It was noted that the concave side of the LD was subjected to greater stress under the neutral standing or LLB load compared with convex side. Additionally, the concave side of the LD was subjected to greater stress under the LLB or RLB load compared with that of other discs. Interestingly, the same trends were observed for the convex side of the LD.

Conclusions: FCRV caused LD to take on greater stress magnitudes. The stress showed a trend of local concentration, which was in the concave side of the scoliosis. These findings could contribute to further treatment planning for the patient and aid physicians' management decision-making.

Objective: Despite several surgical options, there has yet to be a consensus on the best treatment for femoral neck fracture (FNF) due to higher complication rates compared to other bone fractures. This study aims to examine the possible consequences and solution suggestions of changing screws during surgery for various reasons in FNF surgical treatment from a biomechanical perspective.

Method: FNF and treatment materials were analyzed biomechanically using a package program based on the finite element method (FEM). This study created a solid model with images of femur bone tomography. Dynamic hip screws (DHS), cannulated screws (CCS), and medial buttress plates (MBP) were obtained by making three-dimensional designs. The required elements for the models were assigned, and the material properties of the elements were defined. The solutions were obtained as crack distance and deformation results after defining the boundary conditions and applying the necessary loading.

Results: The strain and crack distance values created by six models on the fracture line under different parameters were obtained, and the numerical results were evaluated. The DHS and CCS models produced the highest crack distance and deformation values when all screws were loose. The lowest values were obtained in the intact-85 model when all CCS were tight. When the results are evaluated, it is seen that the MBP has a decreasing effect on the results. Mechanical evaluation of six different options used in femoral neck fractures was performed. 85 mm CCS applied to our standard model gave the best results, while the use of 80 mm CCS in the same model showed promising results compared to other models. It is understood that CCS have the best stability even in loosening models with the medial support plate. Different models are from intact-85 mm DHS+1CS+MBP to DHS+1CS, which was worked with LSR+USR-2, according to decreasing stability.

Conclusion: This study offers various biomechanical solutions to possible intraoperative problems in FNF treatment. The following results were obtained from the study data. When the CCS needs to be lengthened or replaced, it is appropriate to use the CCS with the MBP. A single anti-rotation screw is sufficient for lag screw extensions of the DHS plate, and the MBP may be a savior procedure in surgery.

Objective: The influence of the graft sagittal inclination angle (SIA) on knee stability, biomechanics, and graft maturity has been elucidated. However, no study has comprehensively described the effects of SIA on the aforementioned postoperative prognostic indicators. So, we aimed to determine whether the sagittal inclination angle (SIA) of a graft is associated with postoperative graft maturity, joint stability, and joint function after anterior cruciate ligament (ACL) reconstruction.

Methods: Patients who had undergone ACL reconstruction between April 2019 and February 2022 and those with intact ACL were eligible. Using magnetic resonance imaging, graft maturity was evaluated as the mean signal-to-noise quotient (SNQ) measured in three regions. Anterior tibial translation (ATT) was used to evaluate knee stability. Correlation analysis was conducted for the SIA, ATT, and clinical outcome scores. Multivariate stepwise regression analysis was used on the SIA and potential risk factors to determine their association with the graft SNQ. The SIA threshold of knee instability was calculated by receiver-operating characteristic curves.

Results: Sixty-three postoperative patients were enrolled. The SIA was significantly negatively associated with graft SNQ value. A multivariate stepwise regression analysis showed that SIA and body mass index were significant influencing factors associated with the graft SNQ. Correlations between the SIA and medial and lateral ATT were statistically significant. A larger SIA resulted in a decreased probability of medial and lateral ATT ≥ 5 mm. The SIA threshold of an increased risk of lateral ATT ≥ 5 mm was < 44.4°. A positive correlation was observed between SIA and subjective symptom subscales in the KOOS.

Conclusions: A low SIA is not conducive to graft maturation after ACL reconstruction. A larger graft SIA was correlated with better postoperative knee stability. However, the effect of the SIA on joint function was only significant in terms of symptoms. Therefore, these new findings provide new ideas for preoperative assessment and intraoperative determination of the ideal graft inclination.

Objective: Central cord syndrome (CCS) is an incomplete spinal cord injury (SCI) causing severe motor weakness, and timely decompression via surgical intervention facilitates better recovery. Anterior controllable antedisplacement and fusion (ACAF) is a novel decompression technique and achieved satisfactory outcomes in treating cervical degenerated diseases. However, the clinical effects of ACAF on CCS remains unknown. This present study aimed to investigate the clinical outcomes of ACAF for cervical stenosis patients with CCS due to hyperextension injury.

Methods: This is a retrospective study, and patients who underwent ACAF due to CCS in our institution from July 2021 to December 2022 were enrolled based on the inclusion and exclusion criteria. All patients underwent x-ray, computed tomography (CT), and magnetic resonance imaging (MRI) before and after surgery. The duration of follow-up was at least 12 months. The radiological parameters included associated pathologies, prevertebral hyperintensity (HI), intramedullary signal intensity (ISI), and Torg-Pavlov ratio (TPR). The cervical stability was also evaluated. Neurological function was assessed using the American Spinal Injury Association (ASIA) grading system and Japanese Orthopaedic Association (JOA) score. The Mann-Whitney U test was used to compare the clinical outcomes preoperatively and postoperatively.

Results: Finally, 13 patients (7 male and 6 female) with the minimum of 12-month follow-up were finally enrolled in this study, with the mean age of 56.6 ± 12.5 years (range, 39-74 years). There were eight patients suffered CCS due to fall, three due to vehicle accident, and two due to diving injuries. The average delay from injury to surgery was 2.23 days (range, 1-4 days), and the mean duration of follow-up was 16.1 ± 3.5 months. In terms of prevertebral HI and ISI, C4-C6 were the most affected region. In addition, 76.9% (10 of 13) patients were observed to have cervical stenosis indicated by TPR. Associated pathologies were herniated nucleus pulposus (HNP) in five patients, OPLL in three cases, and HNP-osteophyte complexes (HNP-OC) in six patients. At the final follow-up, 13 patients were improved to E. The mean JOA score improved to 15.4 ± 1.0, with the recovery rate of 77.0% ± 12.0%. Two patients experienced postoperative dysphagia, two patients had hoarseness, and one patient suffered postoperative hematoma.

Conclusions: ACAF can be a good option for treating CCS patients due to hyperextension injury with underlying cervical spondylosis and stenosis.