Conversion of Fused Hip to Total Hip Arthroplasty: Long-Term Clinical and Radiological Outcomes

Functional Improvement and Patient Satisfaction Following Conversion of Fused Hip to Total Hip Arthroplasty

BACKGROUND

This study aimed to determine the clinical outcomes, predictors of suboptimal functional improvement, and factors influencing patient satisfaction following conversion of a fused hip to total hip arthroplasty (THA).

METHODS

A retrospective analysis of clinical and radiographic data was performed on 83 patients (83 hips) who underwent fused hip conversion to THA. Implant survival and predictors of poor functional outcome (Harris hip score < 70) were analyzed. In addition, factors associated with patient dissatisfaction (visual analog scale < 25th percentile) were analyzed in 63 patients (63 hips) who completed a patient-reported outcome measures questionnaire.

RESULTS

The median Harris hip score improved from 55 (range, 18 to 77) to 78 (range, 36 to 100) at a mean follow-up of 10.2 ± 4.8 years (P < .001). Implant survival was 97.4% at 10 years and 91.3% at 20 years, with any revision as the endpoint. Multivariate analysis identified preoperative reliance on mobility aids as an independent predictor of poor functional outcome (P = .021). There were 48 of 63 patients (76%) satisfied (satisfaction visual analog scale ≥80) with the operated hip. Demographics and preoperative/postoperative clinical data did not differ between satisfied and unsatisfied patients. Among the patient-reported outcome measures, the Forgotten Joint Score-12 emerged as an independent discriminator of patient satisfaction.

CONCLUSIONS

Conversion of a fused hip to THA provides functional improvement, favorable implant survival, and high patient satisfaction. However, patients dependent on mobility aids may experience suboptimal functional recovery, underscoring the need for careful preoperative counseling and patient selection.

Neurovascular Structural Deviations in Patients Who Have Fused Hips: Implications for Total Hip Arthroplasty

BACKGROUND

The purpose of this study was to compare the fused and normal sides of patients who have fused hips to determine the differences in neurovascular structures and factors that increase the risk of neurovascular injury.

METHODS

We evaluated 38 patients who underwent total hip arthroplasty, with a fused hip between 2003 and 2021. Excluding patients who had bilateral lesions, differences in the location of neurovascular structures were measured by comparing the fused side with the normal side. The position of neurovascular structures was measured by the distance from the acetabular rim and the shortest distance to the particular bony structure. In addition, the patient's sex, weight, body mass index cause of fused hips, estimated age of fusion onset, and preoperative range of motion were investigated to examine the correlations with neurovascular deviation and these factors.

RESULTS

The neurovascular distances for all the measured neurovascular structures were significantly reduced on the fused side compared with the normal side. Sex-based analysis revealed that women had significantly shorter distances to the femoral neurovascular bundle than men. Although height and body weight were associated with differences in neurovascular distances, body mass index was not associated with significant differences, except for the femoral nerve distance from the nearest bone. When classified by the estimated age of fusion onset, significant differences in neurovascular distances were found between the adolescent- and adult-onset groups.

CONCLUSIONS

In patients who have fused hips, neurovascular structures are located closer to the bone than on the normal side. Moreover, patients in whom the fusion occurred before the completion of growth may exhibit a shorter neurovascular distance, thereby increasing the potential risk of direct injury during total hip arthroplasty .

Long-term outcomes of converting fused hips to total hip arthroplasty are satisfactory: a systematic review and meta-analysis

Background

Although conversion arthroplasty of fused hips can relieve pain and provide patient satisfaction, long-term outcomes of total hip arthroplasty (THA) after hip fusion remain a subject of debate. This meta-analysis aimed to assess the effectiveness of THA for fused hips over a long period with concerns over potential complications.

Methods

A systematic search of five databases from 2000 until 2023 identified English studies evaluating THA for fused hips with at least 100 months of follow-up. Meta-analyses were conducted using random-effect models via the comprehensive meta-analysis software. Sensitivity analysis, in-depth meta-regression, Egger's test, and the trim-and-fill method were performed appropriately.

Results

The meta-analysis assessed 790 patients and 889 hips with a mean follow-up of 11 years. At the final follow-up, the mean Harris Hip Score (HHS) and leg length discrepancy (LLD) improved by 34.755 and 2.3 cm from the baseline, respectively. Regarding survival of hip fusion conversion to THA, most studies (88.8%) reported a 5-year implant survival rate of at least 90%, and the 15-year and 20-year implant survival rates, ranged between 80-90% and 70-90%, respectively. Subjective dissatisfaction with the conversion of hip fusion to THA was only 5.3%. Composite rates of revision, instability, and aseptic loosening were 13.6%, 3.8%, and 8.8%, respectively.

Conclusions

Conversion of fused hips to THA results in favourable long-term outcomes regarding HHS, LLD, survival rates, and subjective satisfaction, leading to improved quality of life in properly selected patients. However, the presence of complications should be considered when evaluating the overall success of the procedure.

Short- to Mid-Term Clinical and Radiological Results of Selective Laser Melting Highly Porous Titanium Cup in Primary Total Hip Arthroplasty

(1) Background: The aim of this study was to evaluate short- to mid-term clinical and radiological results in patients undergoing primary total hip arthroplasty (THA) with the use of a Selective Laser Melting 3D-printed highly porous titanium acetabular cup (Jump System Traser®, Permedica Orthopaedics). (2) Methods: We conducted a retrospective study and collected prospective data on 125 consecutive patients who underwent primary THA with the use of highly porous titanium cup. Each patient was evaluated preoperatively and postoperatively with a clinical and radiological assessment. (3) Results: The final cohort consisted of 104 patients evaluated after a correct value of 52 (38-74) months. The median Harris Hip Score (HHS) significantly improved from 63.7 (16-95.8) preoperatively to 94.8 (38.2-95.8) postoperatively (p < 0.001), with higher improvement associated with higher age at surgery (β = 0.22, p = 0.025). On postoperative radiographs, the average acetabular cup inclination and anteversion were 46° (30°-57°) and 15° (1°-32°), respectively. All cups radiographically showed signs of osseointegration with no radiolucency observed, or component loosening. (4) Conclusions: The use of this highly porous acetabular cup in primary THA achieved excellent clinical, functional, and radiological results at mid-term follow-up. A better clinical recovery can be expected in older patients. The radiological evaluation showed excellent osseointegration of the cup with complete absence of periprosthetic radiolucent lines.

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.

Arthroscopic capsular release for frozen shoulder: when etiology matters

PURPOSE

No therapeutic intervention is universally accepted for frozen shoulder, and the most effective management to restore motion and diminish pain has yet to be defined. The aim of this study was to investigate functional and psychological outcomes in patients who underwent arthroscopic capsular release for a frozen shoulder.

METHODS

A retrospective study with prospective data collection was conducted with 78 patients suffering from frozen shoulder resistance to conservative treatment. Considering the etiology, there were 36 (46.2%) idiopathic, 31 (39.7%) postoperative, and 11 (14.1%) posttraumatic cases. Preoperatively, each patient was evaluated with the range of motion (ROM) assessment and the Constant-Murley score (CMS). At follow-up, the 4-point subjective satisfaction scale (SSS), the ROM assessment, the SF-12 questionnaire, the numerical rating scale (NRS) for the subjective assessment of pain, the CMS and the Hospital Anxiety and Depression Scale (HADS) were assessed.

RESULTS

After a mean follow-up of 54.2 ± 22.3 months, ROM and CMS showed a statistically significant improvement between pre- and postoperative values (all p < 0.001). Before surgery, the mean CMS was 36.9% that of sex- and age-matched healthy individuals, and all patients showed a CMS lower than the normative data. At the final follow-up visit, the mean CMS was 99.9% that of sex- and age-matched healthy individuals, and 49 (62.8%) patients showed a CMS equal to or higher than the normative data. The mean increase in the CMS was 56.1 ± 8.3 points. The mean SSS, HADS-A, HADS-D, and NRS were 3.7 ± 0.5, 2.5 ± 1.6, 2.2 ± 1.3, and 2.2 ± 1.0, respectively. All patients returned to their previous level of work and sports activity after 2 and 2.5 months, respectively. The multivariate analysis showed the association between a higher postoperative CMS and the idiopathic etiology of a frozen shoulder (p = 0.004, β = 3.971). No intraoperative complications occurred. Postoperatively, four patients (5.1%) were treated with intra-articular steroid injections to manage residual symptoms. One patient (1.3%) with a postoperative frozen shoulder showed persistent symptoms and underwent a new successful arthroscopic capsular release.

CONCLUSION

High patient satisfaction and statistically significant ROM and CMS recovery can be achieved after arthroscopic capsular release to manage frozen shoulder. Better functional outcomes are expected when the etiology is idiopathic. Results can help surgeons identify the patients who will most benefit from surgery and should be discussed with the patient.

LEVEL OF EVIDENCE

III.

A Matched Comparison of the Rates of Achieving the Minimal Clinically Important Difference Following Conversion and Primary Total Hip Arthroplasty

BACKGROUND

Patient-reported outcome measures (PROMs) are often lower following conversion total hip arthroplasty (cTHA) compared to matched primary total hip arthroplasty (THA) controls. However, the minimal clinically important differences (MCIDs) for any PROMs are yet to be analyzed for cTHA. This study aimed to (1) determine if patients undergoing cTHA achieve primary THA-specific 1-year PROM MCIDs at comparable rates to matched controls undergoing primary THA and (2) establish 1-year MCID values for specific PROMs following cTHA.

METHODS

A retrospective case-control study was conducted using 148 cases of cTHA which were matched 1:2 to 296 primary THA patients. Previously defined anchor values for 2 PROM measures in primary THA were used to compare cTHA to primary THA, while novel cTHA-specific MCID values for 2 PROMs were calculated through a distribution method. Predictors of achieving the MCID of PROMs were analyzed through multivariate logistic regressions.

RESULTS

Conversion THA was associated with decreased odds of achieving the primary THA-specific 1-year Hip dysfunction and Osteoarthritis Outcome Score for Joint Replacement PROM (Odds Ratio: 0.319, 95% Confidence Interval: 0.182-0.560, P < .001) and Patient Reported Outcomes Measurement Information System Physical Function Short-Form-10a PROM (Odds Ratio: 0.531, 95% Confidence Interval: 0.313-0.900, P = .019) MCIDs in reference to matched primary THA patients. Less than 60% of cTHA patients achieved an MCID. The 1-year MCID of the Hip dysfunction and Osteoarthritis Outcome Score for Joint Replacement and Patient Reported Outcomes Measurement Information System Physical Function Short-Form-10a specific to cTHA were +10.71 and +4.68, respectively.

CONCLUSION

While cTHA is within the same diagnosis-related group as primary THA, patients undergoing cTHA have decreased odds of achieving 1-year MCIDs of primary THA-specific PROMs.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Trend of Perioperative CRP (C-Reactive Protein) Levels in Non-Infected Total Knee Arthroplasty

The aim of this prospective study was to define the perioperative trend of C-reactive protein (CRP) in non-infected total knee arthroplasty (TKA). CRP was evaluated in 42 patients the day before surgery and 4 and 30 days after surgery. Functional and radiological evaluation was scheduled for 3, 6, and 12 months after surgery. Preoperatively, the median CRP was 3.2 mg/L (IQR,3.2-4.2) (reference range, 0-5 mg/L); 4 and 30 days after surgery, it measured 57.6 mg/L (IQR,36.1-96.4) and 5.3 mg/L (IQR,3.0-11.8), respectively. There were significant differences between the CRP preoperatively and 4 days after surgery (p<0.001) and between CPR levels 4 and 30 days after surgery (p<0.001) but not between CRP values preoperatively and 30 days after surgery (p=0.181). Higher preoperative CRP was associated to heart disease and chronic renal failure (r=0.329, p=0.036, and r=0.437, p=0.004, respectively). Four days after surgery, higher CRP was associated to older patients (r=0.311, p=0.048). In summary, 30 days after primary non-infected TKA, CRP levels were comparable to preoperative values. Older age and comorbidities should be carefully evaluated using postoperative CRP as diagnostic marker for the early detection of infection.

Periprosthetic ankle infection: eradication rate, complications, and limb salvage. A systematic review

BACKGROUND

This systematic review investigated the outcomes of revision surgery after periprosthetic ankle infection (PAI).

METHODS

According to the PRISMA statement, 9 studies with 131 PAIs surgically treated and analyzed were included. Demographics and surgical techniques with eradication rates and complications were reported.

RESULTS

Methicillin-sensitive Staphylococcus aureus (MSSA) (30.4%) and coagulase-negative Staphylococcus (CNS) (26.5%) were the most common microorganisms. The eradication rate was 91.7% with permanent antibiotic spacers (SPC), 84.4% with 2-stage, 79.4% with arthrodesis (AA), and 58.8% with debridement and implant retention (DAIR). DAIR showed a significantly lower eradication rate than 2-stage (p = 0.016) and SPC (p = 0.043). Amputations occurred in 25% of patients after SPC, 8.8% after AA and 3.9% after DAIR. SPC showed a significantly higher amputation rate than DAIR and 2-stage (p = 0.044, and p = 0.017, respectively).

CONCLUSIONS

SPC and 2-stage revision show the highest eradication rates, but 2-stage has a lower risk of amputation.

MAKO robotic assisted total hip replacement (THR) for patients with fused hips

BACKGROUND

Previous articles about MAKO robotic-assisted total hip replacement (THR) were mainly in patients with comparatively normal anatomy.

METHODS

From July 2020 to June 2021, we performed MAKO robotic-assisted THR in three hip-fused patients. We assessed the accuracy of prostheses implantation, collected clinical data, and discussed the value of this technique in this kind of patients.

RESULT

All three patients achieved good leg length and prostheses position. A patient got femoral artery injury during the surgery. Moreover, she developed a thrombus. All three patients got acceptable Visual Analogue Scale scores and function recovery 6 months later.

CONCLUSION

MAKO robotic-assisted THR achieved excellent prosthesis position in hip fused patients. More cases are needed to confirm this advantage. The function recovery was acceptable. Caution should be paid to protect the surrounding abnormal arteries, especially in a limited surgical field.

Outcomes of Bi-unicompartmental Versus Total Knee Arthroplasty for the Treatment of Medial and Lateral Knee Osteoarthritis: A Systematic Review and Meta-analysis of Comparative Studies

PURPOSE

The aim of this meta-analysis was to evaluate differences in functional outcomes between simultaneous bi-unicompartmental knee arthroplasty (Bi-UKA) and total knee arthroplasty (TKA) for the treatment of medial and lateral knee osteoarthritis.

MATERIAL AND METHODS

According to the PRISMA statement, a comprehensive search was conducted to identify studies reporting comparative results of the Bi-UKA versus the TKA. Of 953 titles, 6 studies met the inclusion criteria.

RESULTS

A total of 286 patients were identified, of which 137 underwent Bi-UKA and 149 TKA. TKA reported a mean hip-knee-ankle (HKA) angle of 179.4 ± 2.4 compared to that in Bi-UKA measuring 177.2 ± 2.7 (p = 0.0001, 95% CI - 3.02 to - 1.38). No difference was found in the Western Ontario and McMaster Universities (WOMAC) pain (4 ± 1.6 and 4.2 ± 1.3 for Bi-UKA and TKA, respectively; p = 0.4996, 95% CI - 0.86 to 0.43). Bi-UKA was favorable in terms of WOMAC function (7.5 ± 1.9 and 9 ± 1.9 for Bi-UKA and TKA, respectively; p = 0.001, 95% CI - 2.29 to - 0.61) and WOMAC stiffness (1.6 ± 1 and 2.4 ± 0.7 for Bi-UKA and TKA, respectively; p = 0.0001, 95% CI - 1.18 to - 0.42). Bi-UKA showed a better Knee Society Score (KSS) in comparison to TKA (79.7 ± 7.8 and 75.4 ± 10.5 for Bi-UKA and TKA, respectively; p = 0.0021, 95% CI 1.58-7.02). The differences in postoperative outcomes scores between Bi-UKA and TKA were lower than their respective minimum clinically important differences.

CONCLUSIONS

When Bi-UKA and TKA are compared for the treatment of medial and lateral knee osteoarthritis, Bi-UKA are favorable in terms of WOMAC and KSS even though these values are lower than the minimum clinically important differences; moreover, similar postoperative hip-knee-ankle angle can be expected 3 years after Bi-UKA and TKA.

Conversion of a Fused or Ankylosed Hip to Total Hip Arthroplasty: Is the Direct Anterior Approach in the Lateral Decubitus Position an Ideal Solution?

Background

Total hip arthroplasty (THA) using the direct anterior approach (DAA) is becoming increasingly popular due to its potential benefits over the posterolateral approach (PLA). However, few studies have compared the efficacies of these two surgical approaches in hip fusion treatment. This study compared early clinical direct anterior and posterolateral THA outcomes in hip fusion treatment.

Methods

Here, 127 hips (65 DAA, 62 PLA) were retrospectively evaluated. Early postoperative functional outcomes of DAA and PLA groups were assessed using Harris score and Oxford Hip Score (OHS) and standard anteroposterior hip radiographs. Surgical characteristics, perioperative results, and complications within 6 months postoperatively were recorded.

Results

Though baseline values were similar, Harris and OHS scores were better in the DAA group than in the PLA group at 1 and 3 months postoperatively. The average cup anteversion angle was significantly greater in the DAA group than in the PLA group (12.7° vs. 11.1°). More hips undergoing DAA were successfully orientated in both inclination and anteversion angles (46 vs. 32). Early postoperative hip function predictors were preoperative fused hip position, surgical approach, and range of motion. DAA was associated with reduced postoperative blood loss and shorter hospital stays. Furthermore, 14 vs. 8 complications occurred in the DAA vs. PLA group. Lateral femoral cutaneous nerve injuries were observed in eight hips (12.3%) of the DAA group.

Conclusion

For fused or ankylosed hips, THA using DAA in the lateral decubitus position may result in excellent prosthesis positioning and faster postoperative recovery throughout early follow-up vs. PLA.

Posterior versus lateral surgical approach: functionality and quality of life after total hip arthroplasty in a matched cohort study

BACKGROUND

One of the most controversial aspects for maximizing outcomes after total hip arthroplasty (THA) remains the surgical approach to the hip joint. The posterior (PA) and lateral approaches (LA) are the two most commonly performed approaches used worldwide, but sparse data are available for their comparison in terms of health-related quality-of-life (HRQoL). The aim of this study was to assess the role of the PA and LA in the HRQoL and hip functionality of patients who underwent primary and elective THA for osteoarthritis, after a minimum 2-year follow-up.

METHODS

One hundred twenty-eight patients (140 THAs: 68 with PA and 72 with LA) were evaluated in a matched cohort study. Data gathered included the body mass index, the American Society of Anesthesiologists score, surgery time, serum creatine phosphokinase (CpK) levels, estimated intraoperative blood loss and intra- or postoperative complications. Preoperatively and at the last follow-up, the activities of daily living, and the instrumental activities of daily living (IADL) scales, the Western Ontario and Mac Master University (WOMAC) Questionnaire, the Harris Hip Score (HHS) and the Visual Analogue Scale (VAS) were used to assess HRQoL and functionality. The Short Form-36 Health Survey (SF-36) Questionnaire was administered at the last follow-up.

RESULTS

Postoperatively, CpK was higher in the LA group compared to the PA (695 ± 648 vs. 447 ± 326 UI/L, p < 0.001). At a mean follow-up of 47 ± 22 months for the LA group and 42 ± 29 months for the PA group, IADL, VAS, HHS and WOMAC scores significantly improved for both groups (all p < 0.001), but PA reported better VAS, residual pain and WOMAC scores (p = 0.002, p = 0.004 and p = 0.018, respectively). The PA group demonstrated a significant higher mental SF-36 subscale values than the LA group (49 ± 13 vs. 42 ± 19, p = 0.001). The LA group showed a higher number of Trendelenburg signs (p = 0.029). On the contrary, the PA group showed a higher number of leg lengthening (p = 0.020); however, most of these cases was less than the clinically significant value of 10 mm (p = 0.738).

CONCLUSIONS

Patients who underwent THA performed with the PA reported greater improvement in HRQoL with lower residual pain, postoperative muscle damage and Trendelenburg signs than those who underwent the LA.

Review of complications, functional outcome, and long-term survival following conversion of hip fusion to total hip arthroplasty

AIMS

Improvements in functional results and long-term survival are variable following conversion of hip fusion to total hip arthroplasty (THA) and complications are high. The aim of the study was to analyze the clinical and functional results in patients who underwent conversion of hip fusion to THA using a consistent technique and uncemented implants.

METHODS

A total of 39 hip fusion conversions to THA were undertaken in 38 patients by a single surgeon employing a consistent surgical technique and uncemented implants. Parameters assessed included Harris Hip Score (HHS) for function, range of motion (ROM), leg length discrepancy (LLD), satisfaction, and use of walking aid. Radiographs were reviewed for loosening, subsidence, and heterotopic ossification (HO). Postoperative complications and implant survival were assessed.

RESULTS

At mean 12.2 years (2 to 24) follow-up, HHS improved from mean 34.2 (20.8 to 60.5) to 75 (53.6 to 94.0; p < 0.001). Mean postoperative ROM was flexion 77° (50° to 95°), abduction 30° (10° to 40°), adduction 20° (5° to 25°), internal rotation 18° (2° to 30°), and external rotation 17° (5° to 30°). LLD improved from mean -3.36 cm (0 to 8) to postoperative mean -1.14 cm (0 to 4; p < 0.001). Postoperatively, 26 patients (68.4%) required the use of a walking aid. Complications included one (2.5%) dislocation, two (5.1%) partial sciatic nerve injuries, one (2.5%) deep periprosthetic joint infection, two instances of (5.1%) acetabular component aseptic loosening, two (5.1%) periprosthetic fractures, and ten instances of HO (40%), of which three (7.7%) were functionally limiting and required excision. Kaplan-Meier Survival was 97.1% (95% confidence interval (CI) 91.4% to 100%) at ten years and 88.2% (95% CI 70.96 to 100) at 15 years with implant revision for aseptic loosening as endpoint and 81.7% (95% CI 70.9% to 98.0%) at ten years and 74.2% (95% CI 55.6 to 92.8) at 15 years follow-up with implant revision for all cause failure as endpoint.

CONCLUSION

The use of an optimal and consistent surgical technique and cementless implants can result in significant functional improvement, low complication rates, long-term implant survival, and high patient satisfaction following conversion of hip fusion to THA. The possibility of requiring a walking aid should be discussed with the patient before surgery. Cite this article: Bone Joint J 2021;103-B(7 Supple B):129-134.