Complications in Patients Undergoing Spinal Fusion After THA

Hip Osteoarthritis in Patients Undergoing Surgery for Severe Adult Spinal Deformity: Prevalence and Impact on Spine Surgery Outcomes

BACKGROUND

Hip osteoarthritis (OA) is common in patients with adult spinal deformity (ASD). Limited data exist on the prevalence of hip OA in patients with ASD, or on its impact on baseline and postoperative alignment and patient-reported outcome measures (PROMs). Therefore, this paper will assess the prevalence and impact of hip OA on alignment and PROMs.

METHODS

Patients with ASD who underwent L1-pelvis or longer fusions were included. Two independent reviewers graded hip OA with the Kellgren-Lawrence (KL) classification and stratified it by severity into non-severe (KL grade 1 or 2) and severe (KL grade 3 or 4). Radiographic parameters and PROMs were compared among 3 patient groups: Hip-Spine (hip KL grade 3 or 4 bilaterally), Unilateral (UL)-Hip (hip KL grade 3 or 4 unilaterally), or Spine (hip KL grade 1 or 2 bilaterally).

RESULTS

Of 520 patients with ASD who met inclusion criteria for an OA prevalence analysis, 34% (177 of 520) had severe bilateral hip OA and unilateral or bilateral hip arthroplasty had been performed in 8.7% (45 of 520). A subset of 165 patients had all data components and were examined: 68 Hip-Spine, 32 UL-Hip, and 65 Spine. Hip-Spine patients were older (67.9 ± 9.5 years, versus 59.6 ± 10.1 years for Spine and 65.8 ± 7.5 years for UL-Hip; p < 0.001) and had a higher frailty index (4.3 ± 2.6, versus 2.7 ± 2.0 for UL-Hip and 2.9 ± 2.0 for Spine; p < 0.001). At 1 year, the groups had similar lumbar lordosis, yet the Hip-Spine patients had a worse sagittal vertebral axis (SVA) measurement (45.9 ± 45.5 mm, versus 25.1 ± 37.1 mm for UL-Hip and 19.0 ± 39.3 mm for Spine; p = 0.001). Hip-Spine patients also had worse Veterans RAND-12 Physical Component Summary scores at baseline (25.7 ± 9.3, versus 28.7 ± 9.8 for UL-Hip and 31.3 ± 10.5 for Spine; p = 0.005) and 1 year postoperatively (34.5 ± 11.4, versus 40.3 ± 10.4 for UL-Hip and 40.1 ± 10.9 for Spine; p = 0.006).

CONCLUSIONS

This study of operatively treated ASD revealed that 1 in 3 patients had severe hip OA bilaterally. Such patients with severe bilateral hip OA had worse baseline SVA and PROMs that persisted 1 year following ASD surgery, despite correction of lordosis.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Impact of Hip and Knee Osteoarthritis on Full Body Sagittal Alignment and Compensation for Sagittal Spinal Deformity

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

To investigate the effect of lower extremity osteoarthritis on sagittal alignment and compensatory mechanisms in adult spinal deformity (ASD).

BACKGROUND

Spine, hip, and knee pathologies often overlap in ASD patients. Limited data exists on how lower extremity osteoarthritis impacts sagittal alignment and compensatory mechanisms in ASD.

PATIENTS AND METHODS

In total, 527 preoperative ASD patients with full body radiographs were included. Patients were grouped by Kellgren-Lawrence grade of bilateral hips and knees and stratified by quartile of T1-Pelvic Angle (T1PA) severity into low-, mid-, high-, and severe-T1PA. Full-body alignment and compensation were compared across quartiles. Regression analysis examined the incremental impact of hip and knee osteoarthritis severity on compensation.

RESULTS

The mean T1PA for low-, mid-, high-, and severe-T1PA groups was 7.3°, 19.5°, 27.8°, and 41.6°, respectively. Mid-T1PA patients with severe hip osteoarthritis had an increased sagittal vertical axis and global sagittal alignment ( P <0.001). Increasing hip osteoarthritis severity resulted in decreased pelvic tilt ( P =0.001) and sacrofemoral angle ( P <0.001), but increased knee flexion ( P =0.012). Regression analysis revealed that with increasing T1PA, pelvic tilt correlated inversely with hip osteoarthritis and positively with knee osteoarthritis ( r2 =0.812). Hip osteoarthritis decreased compensation through sacrofemoral angle (β-coefficient=-0.206). Knee and hip osteoarthritis contributed to greater knee flexion (β-coefficients=0.215, 0.101; respectively). For pelvic shift, only hip osteoarthritis significantly contributed to the model (β-coefficient=0.100).

CONCLUSIONS

For the same magnitude of spinal deformity, increased hip osteoarthritis severity was associated with worse truncal and full body alignment with posterior translation of the pelvis. Patients with severe hip and knee osteoarthritis exhibited decreased hip extension and pelvic tilt but increased knee flexion. This examines sagittal alignment and compensation in ASD patients with hip and knee arthritis and may help delineate whether hip and knee flexion is due to spinal deformity compensation or lower extremity osteoarthritis.

Impact of prior spinal fusion surgery on complications and functional outcomes following total hip arthroplasty: an updated systematic review and meta-analysis

PURPOSE

This study aimed to compare the complication rates and functional outcomes between patients with and without a history of spinal fusion undergoing THA.

METHODS

A systematic search was conducted across PubMed, EMBASE, Scopus, and Cochrane databases. Studies that compared adults with and without a history of spinal fusion after primary THA were included. The methodological quality of the studies was evaluated using MINORS criteria. Meta-analyses were performed utilizing mean differences (MD), standardized mean differences (SMD), and odds ratios (OR), along with 95% confidence intervals (CI).

RESULTS

Seventeen studies involving 1,789,356 patients (31,786 in the SF group and 1,757,570 in the Non-SF group) were analyzed. The spinal fusion group exhibited significantly higher rates of dislocation (OR 2.50, 95% CI 1.78-3.52), periprosthetic fracture (OR 1.96, 95% CI 1.39-2.77), overall complications (OR 1.73, 95% CI 1.10-2.71), and revision rates (OR 1.86, 95% CI 1.74-1.99). Furthermore, within the first three months, there was an increased risk of dislocation (OR 4.38, 95% CI 1.36-14.14) and revisions (OR 3.87, 95% CI 1.63-9.18). Longer spinal fusions were significantly associated with a higher risk of dislocations (OR 0.62, 95% CI 0.53-0.71). Additionally, prior spinal fusion was linked to higher levels of pain (SMD 0.11, 95% CI 0.02-0.19) and poorer functional outcomes (MD - 0.09, 95% CI - 0.18 to - 0.00).

CONCLUSIONS

Patients with a history of spinal fusion undergoing THA exhibit increased complication rates, higher levels of pain, and greater functional limitations than those without prior fusion. These findings have significant clinical implications for optimizing perioperative care in high-risk patient populations.

Spinal fusion and total hip arthroplasty: why timing is important

BACKGROUND

There is increasing debate among orthopaedic surgeons over the temporal relationship between lumbar spinal fusion (LSF) and total hip arthroplasty (THA) for patients with hip-spine syndrome. Few large studies have directly compared the results of patients who undergo LSF prior to THA (LSF-THA) to those who undergo LSF after THA (THA-LSF). The current study matched THA patients with a prior LSF to patients who underwent LSF after THA to assess: 90-day and 1-year (1) medical/surgical complications; and (2) revisions.

METHODS

We queried a national, all-payer database to identify all patients undergoing THA between 2010 and 2018 (n = 716,084). The LSF-THA patients and THA-LSF patients were then matched 1:1 on age, sex, Charleson Comorbidity Index, and obesity. Medical/surgical complications and revisions at 90 days and 1 year were recorded. Categorical and continuous variables were analysed utilising t-tests and chi-square, respectively.

RESULTS

LSF-THA patients experienced significantly more postoperative dislocations at 90 days and 1 year compared to THA-LSF patients (p = 0.048 and p < 0.001). There were a similar number of revisions performed for LSF-THA and THA-LSF patients at both 90 days and 1 year (p = 0.183 and p = 0.426). Furthermore, at 1 year, LSF-THA patients experienced more pneumonia (p = 0.005) and joint infection (p = 0.020).

CONCLUSIONS

Prior LSF has been demonstrated to increase the risk of postoperative dislocation in patients undergoing THA. The results of the present study demonstrate increased dislocations with LSF-THA compared to THA-LSF. For "hip spine syndrome" patients requiring both LSF and THA, it may be more beneficial to undergo THA prior to LSF. Arthroplasty surgeons may wish to collaborate with spinal surgeons to ensure optimal outcomes for this group of patients.

Is Timing of Total Hip Arthroplasty and Lumbar Spine Fusion Associated With Risk of Hip Dislocation?

Background

In patients with concomitant hip and lumbar spine disease, the question of which surgery-total hip arthroplasty (THA) or lumbar spine fusion (LSF)-to address first has not been adequately answered. We aimed to evaluate the risk of dislocation after THA in patients with LSF first or after THA.

Methods

Retrospective review utilizing the PearlDiver database querying Current Procedural Terminology codes for LSF in the year prior (LSF first) or in the year after primary or revision THA (THA first). International Classification of Disease codes identified postoperative hip dislocation as our primary outcome variable. Demographic data collected included age, sex, and obesity. Dislocation rates were described as a proportion of the cohort and compared with chi-square tests.

Results

We identified 280,857 primary THA and 42,314 revision THA cases from 2012-2019. Of these, 2090 underwent primary THA and LSF, and 283 underwent revision THA and LSF within a year of each procedure. No differences in age, sex, or obesity between groups were noted. No difference in rate of all-time dislocation for primary THA was noted for the LSF first 51/1429 (3.6%) compared to the THA first 30/661 (4.0%) groups (P = .34), or for revision THA with LSF first 48/204 (23.5%) compared to THA first 27/117 (23.1%) groups (P = 1.0).

Conclusions

There was no difference in the risk of dislocation after primary or revision THA if LSF occurred prior to or after the THA. These findings can help surgeons as they counsel patients with concomitant lumbar spine and hip degeneration.

Patients Who Have Had Three or More Levels Fused During Lumbar Spinal Fusion Have Worse Functional Outcomes After Total Hip Arthroplasty

BACKGROUND

Lumbar spinal fusion (LSF) and total hip arthroplasty (THA) are commonly performed in patients who have concomitant spine and hip pathology. While patients who have three or more levels fused during LSF have increased postoperative opioid consumption after undergoing THA, it is unknown whether the number of levels fused during LSF affects THA functional outcomes.

METHODS

A retrospective study was conducted at a tertiary academic center for patients who underwent LSF first and then had a primary THA performed with a minimum of one-year follow-up for the Hip Disability and Osteoarthritis Outcome Score Joint Replacement (HOOS-JR). Operative notes were reviewed to determine the number of levels fused during LSF. There were 105 patients who underwent one-level LSF, 55 patients underwent two-level LSF, and 48 patients underwent three-or-more-level LSF. No significant differences existed in age, race, body mass index, and comorbidities between the cohorts.

RESULTS

While preoperative HOOS-JR was similar among the three cohorts, patients who had three-or-more-level LSF had significantly lower HOOS-JR scores than patients who had two-level or one-level LSF (71.4 versus 82.4 versus 78.2; P = .010) and a lower delta HOOS-JR (27.2 versus 39.4 versus 35.9; P = .014). Patients who had three-or-more-level LSF had a significantly lower rate of achieving minimal clinically important difference (61.7% versus 87.2% versus 78.7%; P = .011) and the patient acceptable symptom state (37.5% versus 69.1% versus 59.0%; P = .004) for the HOOS-JR, compared to patients who had two-level or one-level LSF, respectively.

CONCLUSIONS

Surgeons should counsel patients who have had three-or-more-level LSF that they may have a lower rate of hip function improvement and symptom acceptability after THA, compared to patients who have had a less number of levels fused during LSF.

"Does order of operation matter in patients who have concomitant hip and spine pathology?"

INTRODUCTION

In patients who have coexisting lumbar spine and degenerative hip disease, there remains uncertainty regarding whether hip or spine surgery should be performed first. We hypothesized that undergoing total hip arthroplasty (THA) would protect against subsequent lumbar spine surgery (LSS) in patients who have 'hip-spine syndrome.'

METHODS

A retrospective cohort study was performed from 2013 to 2021 on patients who had radiographically-confirmed hip osteoarthritis and degenerative lumbar spine pathology, evaluated separately in spine and arthroplasty clinics prior to surgical intervention. Included patients ultimately underwent THA and/or LSS. The primary outcome was survivorship free of LSS or THA after the other was initially performed.

RESULTS

Of 256 patients, 206 (80.5%) underwent THA first. Only 14 of 206 (6.8%) who underwent THA required subsequent LSS, while 31 of 50 (62%) who underwent LSS required subsequent THA, (P<0.001). At 5 years, there was 93.9% survivorship-free of LSS in the THA first group, compared to 44.7% survivorship-free of subsequent THA in the LSS group. Multivariate analyses showed that patients who had THA first had lower odds of undergoing subsequent surgery (Odds Ratio (OR): 0.61, Confidence Interval (CI): 0.52-0.70, P<0.001) compared to those who underwent LSS first. Additionally, those who have higher initial Kellgren Lawrence (KL) grade hip osteoarthritis had lower odds (OR:0.94,CI:0.89-0.99, P=0.04), and those who have progressive neurologic deficits (OR:2.64, CI:1.89-3.7, P<0.001) and neurogenic claudication (OR:1.15, CI:1.06-1.24, P=0.001) had increased odds of undergoing subsequent LSS.

CONCLUSION

'Hip-spine syndrome' patients may receive more initial benefit from undergoing THA, potentially reducing the subsequent need for LSS. The exceptions were those patients who had lower-severity hip osteoarthritis and symptoms of major spinal stenosis.

Does fusion length matter? Total hip arthroplasty dislocation after extension of lumbosacral fusion: a case report

CASE

Hip-spine syndrome is a complex challenge for orthopedic surgeons. We present a 60-year-old female with a history of spinal fusion and total hip arthroplasty. The patient underwent extension of the previous fusion with sacropelvic fixation, and 5 months later she presented with left posterior prosthetic hip dislocation which required sedation and closed reduction.

CONCLUSION

Even with no change in lumbar lordosis or pelvic tilt and adequate acetabular cup position, extension of the fusion construct may predispose patients to dislocation. This may be the result of an increased lever arm acting at the hip joint, thereby leading to instability.

Spinal pathology and outcome post-THA: does segment of arthrodesis matter?

INTRODUCTION

The presence of lumbar spine arthrodesis (SA) is associated with abnormal spinopelvic characteristics and inferior outcome post total hip arthroplasty (THA). However, whether patients with upper segment SA are also at increased risk of complications is unknown. This study aims to (1) determine if upper segment SA is associated with inferior THA outcomes; (2) assess spino-pelvic characteristics; and (3) test whether static or dynamic spinopelvic characteristics correlate with outcome post-THA.

MATERIALS AND METHODS

In this retrospective, case-matched, cohort study from a tertiary referral centre, 40 patients (59 hips) that had undergone both THA and any level of spinal arthrodesis (49 THA-Lumb and 10 THA-Cerv) were compared with 41 patients (59 hips) who had THA-only without known spinal pathology. Spino-pelvic characteristics [including severity of Degenerative-Disc-Disease (DDD); spinal balance and stiffness] and outcome, including patient reported outcome measures (PROMs), at minimum of 1-year post-THA were assessed.

RESULTS

THA-Lumb and THA-Cerv groups had greater number of complications and inferior hip and spinal PROMs compared to THA-Only (p < 0.001). Similar spinopelvic characteristics were seen between the THA-Cerv and THA-Lumb, which were significantly different to the THA-only group. The presence of DDD and unbalanced or stiff spine was associated with increased dislocation and inferior PROMs in the whole cohort.

CONCLUSIONS

THA in the presence of SA, regardless of level, is associated with inferior outcomes and an increased risk for dislocation. The presence of a SA is associated with increased risk of adverse spinopelvic characteristics. Such characteristics were strongly associated with increased dislocation-risk and inferior PROMs. It is likely that these adverse characteristics are the most important adverse predictor, rather than segment of SA per se.

Lumbar spinal fusion does not increase early dislocation risk in primary total hip arthroplasty through the direct anterior approach

INTRODUCTION

Patients with total hip arthroplasty (THA) and a concomitant lumbar spinal fusion (LSF) might have an increased incidence of revision surgery and postoperative complications such as early THA dislocation. The direct anterior approach (DAA) has gained popularity in THA due to its soft tissue-preserving nature and the relatively low dislocation risk. The purpose of the present study was to examine whether LSF patients undergoing minimally invasive THA through the DAA might have an increased risk of prosthetic-related complications compared to matched-control patients without a LSF.

MATERIALS AND METHODS

Patients who underwent THA through the DAA in our institution from January 2014 to December 2018 were identified. A total of 30 primary THA also underwent LSF within 3 months from the initial operation. These patients were randomly matched (1:3) for sex, age, and body mass index with patients who underwent primary THA in our institution without a history of LSF (control group). Peri and postoperative complications, revisions, radiographic and clinical outcomes were assessed retrospectively.

RESULTS

LSF patients who underwent THA through the DAA did not have an increased risk of prosthetic-related complications compared to matched-control subjects without a LSF (6.6% versus 4.4%, P < 0.05). The functional and radiological outcomes were similar between groups.

CONCLUSION

LSF patients undergoing THA could benefit from the DAA similarly to patients without LSF and without increased rate of early THA dislocation. Although the complex interplay between the lumbar spine and hip in THA patients warrants further investigation, the outcomes of THA through the DAA in LSF patients appear promising.

LEVEL OF EVIDENCE

Retrospective case-control study, III.

Spinopelvic Relationship and Its Impact on Total Hip Arthroplasty

The dynamic, complex interaction among the spine, pelvis, and hip is often underappreciated, yet understanding it is vital for both arthroplasty and spinal surgeons. There is an increasing incidence of degenerative hip and spinal pathologies as a result of the ageing population. Furthermore, hip pathology can cause spine pathology and vice versa through “hip-spine” and “spine-hip syndrome.” Consequently, total hip arthroplasty (THA) and spinal fusion surgery, which both affect spinopelvic mobility, are also on the rise. Alteration in spinopelvic motion can affect the orientation of the acetabulum and, therefore, implant positioning in THA, leading to complications such as dislocation, impingement, aseptic loosening, and wear of components. This makes it imperative to assess spinopelvic motion and pelvic tilt prior to patients undergoing THA. In this paper, we explore how the surgeon should proceed to reduce risk of component malalignment, as well as the role of navigation systems in acetabular cup positioning.

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.

Does lumbar spine fusion predispose patients to future total hip replacement?

OBJECTIVE

Hip-spine syndrome has been well studied since it was first described by Offierski and MacNab in 1983. Today, strong evidence links symptoms of hip and spine pathology to postsurgical outcomes. Recent studies have reported increased rates of hip dislocation in patients previously treated with total hip arthroplasty (THA) who had undergone lumbar fusion procedures. However, the effect of this link on native hip-joint degeneration remains an area of ongoing research. The purpose of this study was to characterize the relationship between use of lumbar fusion procedures and acceleration of hip pathology by analyzing the rate of future THA in patients with preexisting hip osteoarthritis.

METHODS

This population-level, retrospective cohort study was conducted by using the PearlDiver research program. The initial patient cohort was defined by the presence of diagnosis codes for hip osteoarthritis. Patients were categorized according to use of lumbar fusion after diagnosis of hip pathology. Survival curves with respect to THA were generated by comparison of the no lumbar fusion cohort with the lumbar fusion cohort. To assess the impact of fusion construct length, the lumbar fusion cohort was then stratified according to the number of levels treated (1-2, 3-7, or ≥ 8 levels). Hazard ratios (HRs) were then calculated for the risk factors of number of levels treated, patient age, and sex.

RESULTS

A total of 2,275,683 patients matched the authors' inclusion criteria. Log-rank analysis showed no significant difference in the rates of THA over time between the no lumbar fusion cohort (2,239,946 patients) and lumbar fusion cohort (35,737 patients; p = 0.40). When patients were stratified according to number of levels treated, again no differences in the incidence rates of THA over the study period were determined (p = 0.30). Patients aged 70-74 years (HR 0.871, p < 0.001), 75-79 years (HR 0.733, p < 0.001), 80-84 years (HR 0.557, p < 0.001), and ≥ 85 years (HR = 0.275, p < 0.001) were less likely to undergo THA relative to the reference group (patients aged 65-69 years).

CONCLUSIONS

Although lumbar fusion was initially hypothesized to have a significant effect on rate of THA, lumbar fusion was not associated with increased need for future THA in patients with preexisting hip osteoarthritis. Additionally, there was no relationship between fusion construct length and rate of THA. Although lumbar fusion reportedly increases the risk of hip dislocation in patients with prior THA, these data suggest that lumbar fusion may not clinically accelerate native hip degeneration.

Pelvic incidence affects postoperative dislocation rate in total hip arthropalsty patients with spinal fusion

PURPOSE

The purpose of this study was to compare the clinical outcome of total hip arthroplasty (THA) with and without spinal fusion (SF), and to evaluate the radiographic characteristics of patients with dislocation after THA.

METHODS

A case-controlled study of 53 patients (67 hips) who underwent both THA and SF was performed. The control group was matched to the SF group by age, gender and body mass index, and 106 patients (134 hips) were selected. Hip function was evaluated using the Japanese Orthopaedic Association (JOA) hip score. In addition, the incidence rates of postoperative complications were determined. Radiograph evaluation included lateral inclination and anteversion of the acetabular component. We also analysed sacral slope (SS), pelvic tilt (PT), and pelvic incidence (PI).

RESULTS

The JOA hip score at final follow up was significantly poorer in the SF group compared to the control group. There were 5 cases of dislocations in the SF group and none in the control group. The anteversion of acetabular cup, PT, and PI were significantly higher in the SF group compare to the control group. In particular, the PI of patients with anterior dislocation were significantly higher compare to those of patients without dislocation.

CONCLUSIONS

Our study showed that SF is a risk factor for a poorer clinical outcome and postoperative dislocation of THA. In addition, the abnormal value of PI may be a risk factor to predict dislocation after THA with SF.

Relieved Low Back Pain after Total Hip Arthroplasty in Patients with Both Hip Osteoarthritis and Lumbar Degenerative Disease

Objective

To investigate the relief of low back pain after hip arthroplasty in patients with hip joint and spinal degenerative diseases, and to discuss the effects of unilateral and bilateral hip surgery on the relief of low back pain.

Methods

In this retrospective study, we followed 153 patients (69 males and 84 females, age: 43–88 years) who had undergone total hip arthroplasty (THA) via a posterolateral approach and also suffered from lumbar degenerative diseases in the period of 2009 to 2019. The inclusion criteria were: (i) patients who had been diagnosed with severe hip degenerative disease and also been diagnosed with lumbar degenerative disease; (ii) patients who had undergone THA surgery; and (iii) patients who were retrospectively recruited. The exclusion criteria were: (i) patients who had undergone lumbar fusion or internal fixation surgery; or (ii) patients who had vascular claudication, history of major trauma, diabetic polyneuropathy, lumbar and pelvic infections, tumor diseases; (iii) or patients who had undergone THA because of femoral neck fracture or ankylosing spondylitis. The improvement of hip joint function and the relief of low back pain (LBP) were studied, and the effect of unilateral and bilateral THA on the relief of LBP were discussed. Hip pain and function were evaluated by the Harris Hip Score (HHS), LBP was evaluated by Visual Analog Scale (VAS), and lumbar function was evaluated by the Japanese Orthopaedic Association (JOA) scoring system.

Results

The average follow‐up time was 44.3 months (24–108 months). All patients recovered smoothly without complications. The LBP VAS of 153 patients decreased from 4.13 ± 1.37 preoperatively to 1.90 ± 1.44 postoperatively. The average HHS increased from 45.33 ± 13.23 preoperatively to 86.44 ± 7.59 postoperatively at the latest follow‐up. According to Japanese Orthopaedic Association scoring system, the proportion of patients with good response to treatment in these 153 patients reached 93.46%. LBP VAS decreased from 4.18 ± 1.38 preoperatively to 1.95 ± 1.49 postoperatively in unilateral group and from 3.94 ± 1.32 preoperatively to 1.73 ± 1.23 postoperatively in bilateral group, respectively. There were only nine patients with persistent or aggravated LBP after operation. Among them, six patients underwent subsequent lumbar surgery (five patients had pain relieved after reoperation and one patient had not) and the other three patients chose conservative treatment for pain.

Conclusion

THA can relieve LBP while relieving hip pain and restoring hip function in patients with both hip and lumbar degenerative disease, thus possibly avoiding further spinal surgery.

Effects of Septal Reduction Therapy on Acute Cardiovascular Events and All-Cause Mortality in Patients with Hypertrophic Cardiomyopathy

Septal reduction therapy (SRT) -i.e. septal myectomy and alcohol septal ablation-has been performed to treat medically refractory hypertrophic cardiomyopathy (HCM) for decades. However, it is largely unknown whether SRT prevents HCM-related cardiovascular events or death. The objective was to examine the effects of SRT on acute cardiovascular events and all-cause mortality in HCM. We performed a propensity score (PS) -matched study using databases that capture all hospitalizations and outpatient visits in New York state. We identified patients with HCM who underwent SRT between 2007 and 2014 (i.e. the SRT group) and those who had never had SRT but had at least one hospitalization for HCM during the same period (i.e. the control group). We performed PS matching at a 1:1 ratio. The primary outcome was a composite of acute cardiovascular events and all-cause mortality during 0-180 days and 181-360 days. The secondary outcome was 180- and 360-day all-cause mortality. We included 846 patients with HCM (423 PS-matched pairs). Patients who underwent SRT had a lower risk of the primary outcome event (0-180 days: odds ratio [OR], 0.54; 95% confidence intervals (CI), 0.37-0.80; P = 0.002 and 181-360 days: OR, 0.33; 95% CI, 0.22-0.51; P < 0.0001). Furthermore, the risk of all-cause mortality was lower at 180 days (OR, 0.37; 95% CI, 0.22-0.63; P = 0.0003) and 360 days post-SRT (OR, 0.32; 95% CI, 0.20-0.51; P < 0.0001). In conclusion, our PS-matched study using population-based datasets demonstrated that SRT was associated with a reduced risk of a composite of acute cardiovascular events and all-cause mortality in HCM during the first post-SRT year.

Dislocation rates following total hip arthroplasty via the direct anterior approach in a consecutive, non-selective cohort

AIMS

Use of the direct anterior approach (DAA) for total hip arthroplasty (THA) has increased in recent years due to proposed benefits, including a lower risk of dislocation and improved early functional recovery. This study investigates the dislocation rate in a non-selective, consecutive cohort undergoing THA via the DAA without any exclusion or bias in patient selection based on habitus, deformity, age, sex, or fixation method.

METHODS

We retrospectively reviewed all patients undergoing THA via the DAA between 2011 and 2017 at our institution. Primary outcome was dislocation at minimum two-year follow-up. Patients were stratified by demographic details and risk factors for dislocation, and an in-depth analysis of dislocations was performed.

RESULTS

A total of 2,831 hips in 2,205 patients were included. Mean age was 64.9 years (24 to 96), mean BMI was 29.2 kg/m² (15.1 to 53.8), and 1,595 patients (56.3%) were female. There were 11 dislocations within one year (0.38%) and 13 total dislocations at terminal follow-up (0.46%). Five dislocations required revision. The dislocation rate for surgeons who had completed their learning curve was 0.15% compared to 1.14% in those who had not. The cumulative periprosthetic infection and fracture rates were 0.53% and 0.67%, respectively.

CONCLUSION

In a non-selective, consecutive cohort of patients undergoing THA via the DAA, the risk of dislocation is low, even among patients with risk factors for instability. Our data further suggest that the DAA can be safely used in all hip arthroplasty patients without an increased risk of wound complications, fracture, infection, or revision. The inclusion of seven surgeons increases the generalizability of these results. Cite this article: Bone Joint J 2021;103-B(7 Supple B):38-45.

Simulation of Implant Impingement After Spinal Corrective Fusion Surgery in Patients with Previous Total Hip Arthroplasty: A Retrospective Case Series

STUDY DESIGN

A retrospective case series.

OBJECTIVE

The aim of this study was to introduce the prevention of total hip arthroplasty (THA) dislocation using an implant impingement simulation after spinal corrective fusion and to verify the outcomes.

SUMMARY OF BACKGROUND DATA

A high dislocation rate was found among patients who underwent spinal deformity corrective fusion with previous THA. To avoid dislocation, an appropriate position of the stem and cup is important, but the pelvic inclination may change after corrective fusion for spinal deformity.

METHODS

Twelve consecutive patients (two men, 10 women; average age, 72.1 [range, 55-81] years during spine surgery) with previous THA were included. Data were retrospectively retrieved from a single-center's prospectively collected database of adult spinal deformity operation. Before surgery, anterior implant impingement simulation in THA was performed using computed tomography-based software. The tolerable pelvic tilt (PT) in which the anterior implant impingement occurred in the hip at the 120° flexion position was measured. The lumbar lordosis angle was deliberately reduced during spinal surgery according to the tolerable PT. The effect of the implant impingement simulation was verified by comparison with patients who underwent surgery before simulation (before 2014).

RESULTS

THA dislocation occurred in six patients: four of five (80%) in the non-simulation, and two of seven (28.6%) in the simulation group. The difference between the preoperative and tolerable PT angles was-25° to 33°, and three patients had negative angles. In these three patients, the risk of anterior impingement and THA dislocation significantly increased with correction of lumbar lordosis if the PT was anterior. Two patients experienced repeated THA dislocation with postoperative and tolerable PT angle differences of 2° and -23°.

CONCLUSION

Our simulation of anterior implant impingement and subsequent adjustment of the degree of spinal correction was useful to prevent dislocation. However, this method did not prevent dislocation in some patients.Level of Evidence: 4.

Does total hip arthroplasty have a higher risk of failure in patients who undergo lumbar spinal fusion?

AIMS

Total hip arthroplasty (THA) patients undergoing or having a prior lumbar spine fusion (LSF) have an increased risk of mechanical complications. The aim of this registry-based, retrospective comparative cohort study is to assess the longer term survival of THA in patients who have undergone a LSF during a 17-year period (2000 to 2017).

METHODS

A registry-based population study was conducted on 679 patients who underwent both THA and LSF surgeries. Patients were identified from the regional arthroplasty data base and cross linked to patients with LSF from the regional hospital discharge database between 2000 and 2017. Demographic data, diagnosis leading to primary THA, primary implant survival, perioperative complications, number and causes of failure, and patients requiring revision arthroplasty were collated and compared. For comparison, data from 67,919 primary THAs performed during the same time time period were also retrieved and analyzed.

RESULTS

Patients undergoing THA and LSF showed homogeneous demographic data compared to those undergoing THA alone, but a significantly lower eight-year THA implant survival (96.7 vs 96.0, p = 0.024) was observed. Moreover, THA plus LSF patients showed increased incidence of mechanical complications in the first two years after THA surgery compared to THA alone patients.

CONCLUSION

This registry-based population study shows that approximately 679 (1%) THA patients were subjected to LSF. Patients undergoing THA and LSF have an increased risk of mechanical complications with their THA and a slightly increased risk of revision arthroplasty. Cite this article: Bone Joint J 2021;103-B(3):486-491.

[Battle: Indication for surgery in hip-spine syndrome-Hip or spine first? : The spine surgeon's view]

Pathologies of the hip, spine and the lower extremity are often concomitant due to their three-dimensional anatomic and physiological interrelation. The real challenge lies in defining which of the pathologies is most relevant for the patient in terms of clinical symptoms and which organ should be treated first. The purpose of this review article is two-fold: Firstly, to explain the treatment dilemma of hip-spine syndrome to the treating physician. Secondly, to highlight the significance of spinal pathology in this context.

Patients Who Undergo Primary Lumbar Spine Fusion After Recent but Not Remote Total Hip Arthroplasty Are at Increased Risk for Complications, Revision Surgery, and Prolonged Opioid Use

OBJECTIVE

To evaluate the effect of a recent history of total hip arthroplasty (THA) on primary lumbar spine fusion (LSF) for concurrent hip and spine disease.

METHODS

A total of 98,242 patient records from the PearlDiver Database were evaluated and divided into 3 cohorts: 1) patients with a history of LSF alone, 2) patients with a history of LSF for newly diagnosed lumbar disease after having a remote THA> 2 years previously, and 3) patients with a history of LSF after having recent THA <2 years before LSF who initially presented with concurrent hip and lumbar spine disease and underwent THA before LSF. Postoperative outcomes were assessed with multivariable logistic regression to determine the effect of THA on outcomes after LSF with respect to postoperative complications, LSF revision rates, and opioid use.

RESULTS

Patients who had LSF after a recent THA had increased risk of deep venous thrombosis (adjusted odds ratio [aOR], 1.39; P = 0.0191), neurologic complications (aOR, 1.81; P = 0.0459), prolonged opioid use (aOR, 1.22; P = 0.0032), and revision LSF (12.8%; P = 0.0004 vs. 9.9%; OR, 1.41; P < 0.0001; hazard ratio, 1.69; P < 0.0001). Patients who underwent LSF after a remote history of THA had no significant difference in DVT (4.2% vs. 2.6%, aOR, 1.31; P = 0.2190), neurologic complications (1.0% vs. 0.5%, aOR, 2.02; P = 0.1220), revision surgery (9.6% vs. 9.9%, aOR, 1.06; P = 0.7197), or prolonged opioid use (36.5% vs. 24.4%, aOR, 1.17; P = 0.1120).

CONCLUSIONS

Patients who undergo LSF with a history of THA may be at increased risk of postoperative complications, revision LSF, and prolonged opioid use if their THA was performed for concurrent hip-spine disease in the recent past (<2 years).

Outcomes following primary total hip arthroplasty with pre-existing spinal fusion surgery

Aims

There is inconsistent evidence on whether prior spinal fusion surgery adversely impacts outcomes following total hip arthroplasty (THA). We conducted a systematic review and meta-analysis to assess the association between pre-existing spinal fusion surgery and the rate of complications following primary THA.

Methods

We searched MEDLINE, Embase, Web of Science, and Cochrane Library up to October 2019 for randomized controlled trials (RCTs) and observational studies comparing outcomes of dislocation, revision, or reasons for revision in patients following primary THA with or without pre-existing spinal fusion surgery. Furthermore, we compared short (two or less levels) or long (three or more levels) spinal fusions to no fusion. Summary measures of association were relative risks (RRs) (with 95% confidence intervals (CIs)).

Results

We identified ten articles corresponding to nine unique observational studies comprising of 1,992,366 primary THAs. No RCTs were identified. There were 32,945 cases of spinal fusion and 1,752,362 non-cases. Comparing prior spinal fusion versus no spinal fusion in primary THA, RRs (95% CI) for dislocation was 2.23 (1.81 to 2.74; seven studies), revision 2.14 (1.63 to 2.83; five studies), periprosthetic joint infection 1.71 (1.53 to 1.92; four studies), periprosthetic fracture 1.52 (1.28 to 1.81; three studies), aseptic loosening 1.76 (1.54 to 2.01; three studies), and any complications 2.82 (1.37 to 5.80; three studies) were identified. Both short and long spinal fusions, when compared with no fusion, were associated dislocation, revision, or reasons for revision.

Conclusions

Patients with prior spinal fusion are at risk of adverse events following primary THA. Measures that reduce the risk of these complications should be considered in this high-risk population when undergoing primary THA. These patients should also be counselled appropriately around their risks of undergoing THA. Cite this article: Bone Joint J 2020;102-B(6):664–670.

Hip or spine surgery first?: a survey of treatment order for patients with concurrent degenerative hip and spinal disorders

AIMS

Patients may present with concurrent symptomatic osteoarthritis (OA) of the hip and degenerative disorders of the lumbar spine, with surgical treatment being indicated for both. Whether arthroplasty of the hip or spinal surgery should be performed first remains uncertain.

MATERIALS AND METHODS

Clinical scenarios were devised for a survey asking the preferred order of surgery and the rationale for this decision for five fictional patients with both OA of the hip and degenerative lumbar disorders. These were symptomatic OA of the hip and: 1) lumbar spinal stenosis with neurological claudication; 2) lumbar degenerative spondylolisthesis with leg pain; 3) lumbar disc herniation with leg weakness; 4) lumbar scoliosis with back pain; and 5) thoracolumbar disc herniation with myelopathy. This survey was sent to 110 members of The Hip Society and 101 members of the Scoliosis Research Society. The choices of the surgeons were compared among scenarios and between surgical specialties using the chi-squared test. The free-text comments were analyzed using text-mining.

RESULTS

Responses were received from 51 hip surgeons (46%) and 37 spine surgeons (37%). The percentages of hip surgeons recommending 'hip first' differed significantly among scenarios: 59% for scenario 1; 73% for scenario 2; 47% for scenario 3; 47% for scenario 4; and 10% for scenario 5 (p < 0.001). The percentages of spine surgeons recommending 'hip first' were 49% for scenario 1; 70% for scenario 2; 19% for scenario 3; 78% for scenario 4; and 0% for scenario 5. There were significant differences between the groups for scenarios 3 (more hip surgeons recommended 'hip first'; p = 0.012) and 4 (more hip surgeons recommended 'spine first'; p = 0.006).

CONCLUSION

In patients with coexistent OA of the hip and degenerative disorders of the spine, the question of 'hip or spinal surgery first' elicits relatively consistent answers in some clinical scenarios, but remains controversial in others, even for experienced surgeons. The nature of neurological symptoms can influence surgeons' decision-making. Cite this article: Bone Joint J 2019;101-B(6 Supple B):37-44.

Time to Dislocation Analysis of Lumbar Spine Fusion Following Total Hip Arthroplasty: Breaking Up a Happy Home

BACKGROUND

Although a history of lumbar spine fusion (LSF) is associated with increased dislocation risk following total hip arthroplasty (THA), the effect of LSF following THA is not well described. This study sought to describe the dislocation-free survival experience of patients with THA undergoing LSF, compare this to similar patients not undergoing LSF, and assess factors associated with dislocation risk following LSF.

METHODS

Center for Medicare Service billing data from 2005 to 2014 was analyzed utilizing the PearlDiver platform. Patients without evidence of hip instability, defined as no dislocation event within at least 6 months following THA, were identified and stratified by having subsequent LSF. Kaplan-Meier curves were used to describe dislocation-free survival of these groups and assess factors associated with dislocation.

RESULTS

Among 17,223 patients without history of hip instability following THA, there was no spike in dislocations following LSF with patients having a persistent and stable rate of dislocation of 0.7% per year. This experience was of similar shape but increased hazard when compared to that of 863,182 patients not undergoing LSF who had a dislocation rate of 0.4% per year (P < .001). Dislocations were not strongly associated with gender, age, comorbidities, or fusion length.

CONCLUSION

Patients without evidence of hip instability following THA subsequently undergoing LSF do not have a spike in dislocations in the perioperative period but do assume a persistently elevated risk of dislocation. Future research should identify factors responsible for this increased risk to determine whether they may be modifiable.