Cementless total hip arthroplasty in patients with ankylosing spondylitis: A retrospective observational study

Clinical Outcomes and Complications Following Hip Fusion Conversion to Total Hip Arthroplasty: A Systematic Review and Meta-Analysis

BACKGROUND

Efficacy, clinical outcomes, and complications following hip fusion conversion to total hip arthroplasty (THA) surgery have been explored in several studies with controversial findings and no consensus.

METHODS

Comprehensive search of online databases was performed through December 2022 for prepost clinical trials using MeSH keywords. Harris hip score (HHS), leg length discrepancy (LLD), pain score, and range of motion (ROM) were considered as clinical outcomes along with implant survival and complications. The retrieved studies were assessed for methodologic quality. Weighted mean difference (WMD) with 95% confidence interval (CI) were calculated using random effects meta-analysis taking into account for heterogeneity. Subgroup meta-analysis as well as sensitivity analysis were performed.

RESULTS

Findings of meta-analysis on 34 trials showed that HHS increase after THA (WMD: 42.3; 95% confidence interval (CI): 38 to 47). Subgroup analyses indicated that cementless prosthesis, length of arthrodesis <12 years, age <45 years, and studies with good quality have more HHS improvement. The LLD decreased 21 mm (95% CI: 19 to 24 mm) based on 21 trials. The range of motion (ROM) reached to 89 (95% CI: 84 to 95) for flexion, 32 (95% CI: 27 to 37) for abduction, 25 (95% CI: 21 to 29) for adduction, 29 (95% CI: 25 to 33) for external rotation, and 25 (95% CI: 20 to 31) for internal rotation after surgery. The most common complication was heterotopic ossification (14%).

CONCLUSION

Conversion of an ankylosed hip to THA leads to improved hip function and leg discrepancy with relatively notable rate of complications. Our findings could provide a framework to guide surgeons and decision makers.

Ankylosing Spondylitis Patients Have Lower Risk of Dislocation Following Total Hip Arthroplasty Compared with Patients Undergoing Lumbar Spinal Fusion Surgery

Purpose

Patients undergoing lumbar spinal fusion (LSF) surgery and patients with ankylosing spondylitis (AS) have concomitant pathology of hip and lumbosacral spine. The purpose of our study is to compare the dislocation rate following total hip arthroplasty (THA) between patients with LSF and AS and reveal the differences of lumbar fusion secondary to LSF and AS.

Patients and methods

Fifty-nine patients (73 hips) were included in Group LSF and every patient was matched with two patients in Group AS. Follow-ups were conducted for information of surgical prognosis and dislocation events following THA. Multiple anatomic parameters were measured on preoperative and postoperative radiological images.

Results

The dislocation rate of patients in Group AS (0.68%) was obviously lower than that of patients in Group LSF (4.11%) and the hazard ratio of dislocation events following THA reached 6.1. Considering the low calculated power (1-β, 0.24), we supposed insufficient statistical evidence (p=0.118) could be attributed to small sample size. Postoperative hip flexion range of motion (ROM) in Group AS (102.1°±24.5°) was significantly lower than that in Group LSF (117.4°±14.2°) (p<0.0005). Postoperative flexion ROM of lumbar was also significantly lower in Group AS (p<0.001). There was no significant difference between two groups concerning postoperative acetabular inclination (p=0.988) and anteversion (p=0.25). However, patients in Group AS had a significantly lower sacral slope (p=0.025) and higher pelvic tilt (p<0.0005) than patients in Group LSF after THA.

Conclusion

Patients with AS have a lower risk of dislocation after THA compared with patients undergoing LSF. The lower risk is significantly relevant to severer stiffness and lower mobility along the spine-pelvis--hip axis in AS patients after THA. Acetabular orientation has no significant effect on the difference of dislocation rate between patients with LSF and AS.

Functional and clinical outcome with modified lateral approach total hip arthroplasty in stiff hips with ankylosing spondylitis

BACKGROUND

Ankylosing spondylitis at total hip arthroplasty (THA) has significant hip stiffness with flexion deformity, restricted mobility, and function. Range of movement (ROM) improvement with good functional outcome is seen following THA in these hips. The modified Hardinge approach without abductor compromise is helpful in these stiff hips with associated flexion deformity.

AIM

To assess improvement in ROM and functional outcomes with a modified lateral approach THA in ankylosing spondylitis with stiff hips.

METHODS

A total of 69 hips that underwent THA with a modified Hardinge approach in 40 patients were evaluated at a mean follow-up of 38.33 mo. All individuals ambulated with weight-bearing as tolerated and ROM exercises from the 1^st postoperative day. Modified Harris hip score and ROM were assessed during follow-up. Quality of life assessments using the 36-item and 12-item short form health surveys were done along with clinical and functional outcomes at follow-up. SPSS 22.0 was used for statistical analysis. The correlation of ROM and functional score change was performed using Pearson’s correlation coefficient.

RESULTS

Sixty-nine hips with a significant decrease in ROM preoperatively with 32 clinically fused hips showed significant improvement in flexion range. The mean flexion in 69 hips improved from 29.35 ± 31.38 degrees to 102.17 ± 10.48 degrees. The mean difference of 72.82 with a P value < 0.0001 was significant. In total, 45 out of 69 hips had flexion deformity, with 13 hips having a deformity above 30 degrees. The flexion during the follow-up was below 90 degrees in 3 hips. Eleven hips had flexion of 90 degrees at follow-up, while the remaining 55 hips had flexion above 100 degrees. Modified Harris hip score improved from 17.03 ± 6.02 to 90.66 ± 7.23 (P value < 0.0001). The 36-item short form health survey at the follow-up indicated health status in 40 patients as excellent in 11, very good in 20, good in 5, fair in 3, and poor in 1. The mean mental health score was 84.10 ± 11.58. Pain relief was good in all 69 hips. Altogether, 28/40 patients (70%) had no pain, 9 patients (22%) had occasional pain, and 3 patients (8%) had mild to moderate pain with unusual activity. Heterotopic ossification was seen in 21 hips with Brooker class 1 in 14 hips.

CONCLUSION

Modified Hardinge approach THA in ankylosing spondylitis with stiff hips with flexion deformity significantly improved ROM, Harris hip score, and quality of life indicated by the 36-item and 12-item short form health surveys.

Heterotopic Ossification: Clinical Features, Basic Researches, and Mechanical Stimulations

Heterotopic ossification (HO) is defined as the occurrence of extraskeletal bone in soft tissue. Although this pathological osteogenesis process involves the participation of osteoblasts and osteoclasts during the formation of bone structures, it differs from normal physiological osteogenesis in many features. In this article, the primary characteristics of heterotopic ossification are reviewed from both clinical and basic research perspectives, with a special highlight on the influence of mechanics on heterotopic ossification, which serves an important role in the prophylaxis and treatment of HO.

Total hip arthroplasty in fused hips with spine stiffness in ankylosing spondylitis

Ankylosing spondylitis (AS) is characterized by involvement of the spine and hip joints with progressive stiffness and loss of function. Functional impairment is significant, with spine and hip involvement, and is predominantly seen in the younger age group. Total hip arthroplasty (THA) for fused hips with stiff spines in AS results in considerable improvement of mobility and function. Spine stiffness associated with AS needs evaluation before THA. Preoperative assessment with lateral spine radiographs shows loss of lumbar lordosis. Spinopelvic mobility is reduced with change in sacral slope from sitting to standing less than 10 degrees conforming to the stiff pattern. Care should be taken to reduce acetabular component anteversion at THA in these fused hips, as the posterior pelvic tilt would increase the risk of posterior impingement and anterior dislocation. Fused hips require femoral neck osteotomy, true acetabular floor identification and restoration of the hip center with horizontal and vertical offset to achieve a good functional outcome. Cementless and cemented fixation have shown comparable long-term results with the choice dependent on bone stock at THA. Risks at THA in AS include intraoperative fractures, dislocation, heterotopic ossification, among others. There is significant improvement of functional scores and quality of life following THA in these deserving young individuals with fused hips and spine stiffness.

Mid-term results of bilateral synchronous total hip arthroplasty for bony ankylosis in patients with ankylosing spondylitis

Background

Total hip arthroplasty (THA) for bony ankylosis is technically challenging in patients with ankylosing spondylitis (AS). This study aimed to determine the mid-term results of bilateral synchronous THA for bony ankylosis in patients with AS.

Methods

Nineteen cases of bony ankylosis in patients with AS who received bilateral synchronous THA were included in this study (17 males and 2 females, mean age 49.2 years). Disease duration was 5–38 years (mean 18 years and 6 months). All patients received cementless THA. Intraoperative blood loss, visual analog scale (VAS) score, and complications were assessed. Harris hip scores evaluated the clinical effect.

Results

Patients were followed up for 62–98 months (mean 82.5 months). VAS score decreased from 7.42 ± 0.92 to 2.42 ± 0.83, Harris hip score improved from 21.8 ± 7.2 to 80.3 ± 6.5, and the flexion-extension range of the hip improved from 0 to 142.3 ± 6.2°. One patient with septum bronchiale had a fracture intraoperatively and was treated with wire strapping. One patient had a traction injury of the femoral nerve postoperatively and recovered 1 year after the operation. Loosening and subsidence were not observed in all patients. Heterotopic bone formation was noted in 3 patients. No complications such as joint dislocation, acute infection, and deep vein thrombosis were found.

Conclusion

Bilateral synchronous THA was effective for bony ankylosis of the hip in patients with AS because it improved patients’ quality of life and had satisfactory mid-term outcomes.

Short to long term outcomes of 154 cemented total hip arthroplasties in ankylosing spondylitis

BACKGROUND

Long-term outcome of Total Hip arthroplasty (THA) in Ankylosing Spondylitis (AS) remains unreported. Literature suggests a higher overall failure rate in ankylosing spondylitis as compared to osteoarthritis. Concern has been expressed regarding joint survival, given that recipients are generally young. The results of cemented THA in patients with ankylosing spondylitis were studied to determine the utility of THA for these patients.

METHODS

Consecutive series of 96 patients (77 males (80%) and 19 females (20%)) with ankylosing spondylitis who underwent 154 cemented THAs at a tertiary referral orthopaedic centre between January 1990-September 2015 were retrospectively analyzed for clinical and radiological outcomes; 58 patients (60.4%) underwent bilateral surgery.

RESULTS

Mean age at surgery was 48 years. Average follow up was 12.8 (2.1-24.8) years. 95% of the patients had a good or excellent post-operative outcome.Out of the total 154 hips operated on, 11% (17 hips) developed post-operative complications. Overall, 15 hips (9.7%) required a revision of the procedure, with the most common indication being aseptic loosening of the acetabulum. Average time to revision was 8.5 years (2-15). Survivorship analysis revealed probability of survival of both components at the end of 10 years, with revision due to any reason as the end point to be 92% (with 95% confidence intervals).21 hips (14%) developed heterotopic ossification post-operatively, of which 4 patients (2%) had clinically significant ossification (Brooker III or IV).

CONCLUSION

This is one of the largest series of patients with ankylosing spondylitis with long term follow up available. Cemented THA in patients with ankylosing spondylitis provided consistently good and predictable long term results, with low rate of complications and revisions.

A Comparative Study of Patients' Subjective Feelings Toward Total Hip Arthroplasty with Patient-Specific Instruments and Traditional Total Hip Arthroplasty

OBJECTIVE

To determine whether differences exist in patients' subjective feelings, daily life, and surgical satisfaction between those who underwent surgery for developmental dysplasia of the hip (DDH) using patient-specific instruments (PSIs) and those who underwent traditional surgical total hip arthroplasty (THA).

METHODS

We selected 30 adult patients with various types of DDH who underwent surgery during 2016-2017 at our hospital. The patients were divided into PSI surgery group and the traditional surgery group. All patients underwent follow-up, and we collected data on the Harris Hip Score, Oxford University Hip Score (OHS), Forgotten Joint Score (FJS-12), Visual Analogue Scale (VAS) score, patient satisfaction score, intraoperative surgical time, amount of bleeding and postoperative complications incidence for both groups. We then performed statistical analyses on the data.

RESULTS

The Harris Hip Score, OHS, VAS score, patient satisfaction score, and mean bleeding volume did not differ statistically significantly (t-tests, P > 0.05). No statistically significant differences were found between surgical groups in the incidence of complication and sub-trochanteric osteotomy, or in the surgical side (chi-square tests, P > 0.05). For the experimental group, the FJS-12 score was 80.0 ± 12.0, and for the control group the score was 68.5 ± 16.1. The operative time of the experimental group was 138.4 ± 32.2 min, while that of the control group was 88.9 ± 26.8 min. The values of these data differed significantly (t-tests, P < 0.05).

CONCLUSIONS

The novel PSI designed by our group has certain advantages for the short-term subjective feelings of patients after THA, but it may cause prolonged operative times.

Does the Femoral Head Size Influence Outcomes After Uncemented Total Hip Arthroplasty for Fused Hips? A Prospective Study in Ankylosing Spondylitis

BACKGROUND

Uncemented total hip arthroplasty (THA) with large size femoral heads have shown greater advantage with good stability, range of motion and decreased dislocation rate in ankylosing spondylitis (AS). Meticulous planning is needed to address the unique surgical challenges in such patients with fused hip and spinal deformity.

MATERIALS AND METHODS

Thirty fivefused hip joints in twenty-five AS patients who underwent uncemented THA (April 2014 to December 2016) were included in our prospective study and were followed up for a minimum period of 36 months. Pain relief, functional improvement and patient satisfaction were statistically assessed using "Visual Analogue Score" (VAS), "Harris Hip Score" (HHS) and "AJRI 10-Point Satisfaction Score" (A10PSS), respectively.

RESULTS

The overall mean preoperative VAS improved from 6.9 ± 1.5 to 1.5 ± 1, HHS improved from 50.0 ± 12 to 88.4 ± 7.8 and A10PSS improved from 2.2 ± 1.2 to 7.6 ± 0.8. Our study results were significant with zero dislocation and good functional score in comparison to the other available studies in literature. First subdivision study in AS patients with bilateral THA performed better than unilateral THA. Second subdivision study showed no significant statistical difference in terms of VAS, HHS, A10PSS and dislocation rate in relation to femoral head size between 32 mm, 36 mm and 40 mm.

CONCLUSION

Uncemented THA with large size femoral head equal or greater than 32 mm provides better stability and good functional outcome with less dislocation rate in comparison to older studies of literature with femoral head size less than 32 mm.

LEVEL OF EVIDENCE

A Level II study. (Data collected from the ongoing prospective study) (https://www.spine.org/Documents/LevelsofEvidenceFinal.pdf).

Ankylosing spondylitis: etiology, pathogenesis, and treatments

Ankylosing spondylitis (AS), a common type of spondyloarthropathy, is a chronic inflammatory autoimmune disease that mainly affects spine joints, causing severe, chronic pain; additionally, in more advanced cases, it can cause spine fusion. Significant progress in its pathophysiology and treatment has been achieved in the last decade. Immune cells and innate cytokines have been suggested to be crucial in the pathogenesis of AS, especially human leukocyte antigen (HLA)‑B27 and the interleukin‑23/17 axis. However, the pathogenesis of AS remains unclear. The current study reviewed the etiology and pathogenesis of AS, including genome-wide association studies and cytokine pathways. This study also summarized the current pharmaceutical and surgical treatment with a discussion of future potential therapies.

Identification of potential target genes for ankylosing spondylitis treatment

This study aimed to identify the potential target genes for the treatment of ankylosing spondylitis (AS).Dataset GSE25101 was downloaded from Gene Expression Omnibus, including 16 AS and 16 normal control blood samples. Differentially expressed genes (DEGs) were identified using unmatched t-test in limma package with adjusted P < .05. Gene ontology-biological process (GO-BP) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted using multifaceted analysis tool for human transcriptome. Protein-protein interaction (PPI) network was constructed using STRING and Cytoscape, and module analysis was performed using MCODE plug-in. Webgestal was utilized to predict transcriptional factor (TF)-microRNA-target network and Comparative Toxicogenomics Database (CTD) was applied to predict chemical-target network.A total of 334 DEGs were identified, including 136 upregulated genes and 198 downregulated genes. According to STRING, a PPI network was constructed and 1 significant clustered module was screen out with score = 6.33. MAPK7 (degree = 11) and NDUFS4 (degree = 10) were 2 important nodes in PPI network, and both of them were significantly enriched in cAMP mediated signaling pathway (P = 2.02E-02). MAPK7 could be regulated by NFY. Both MAPK7 and NDUFS4 were 2 potential targets for Indomethacin.MAPK7 and NDUFS4 played important roles in the pathogenesis of AS via cAMP mediated signaling pathway. Both of them could be targeted by Indomethacin.