Fused hip conversion to total hip arthroplasty with the direct anterior approach: surgical technique on a regular surgical table under fluoroscopic guidance.

PURPOSE: Conversion of a fused hip to a total hip arthroplasty (THA) is technically challenging due to the loss of anatomical references. Here, a reproducible technique using the direct anterior approach (DAA) with a regular surgical table under fluoroscopic guidance is described, which has several advantages over traditional such as lateral or posterior approaches. METHODS: There were reported 11 cases of ankylosis hip that were converted to THA using the same surgical technique protocol. Clinical and radiographic outcomes were recorded at 3.2 years of follow-up. A detailed preoperative evaluation was performed, including a pelvis radiological evaluation and magnetic resonance image (MRI) to assess the integrity of the periarticular soft tissue and flexor muscles. RESULTS: The DAA has considerable advantages, such as allowing more precise targeting during surgery, avoiding the risk of pseudoarthrosis due to the absence of a trochanteric osteotomy, preserving the abductors, and allowing an easier-to-use of intraoperative fluoroscopy due to the supine position. Besides, the use of a standard table reduces surgical time and allows assessment of limb length, hip stability, and impingement in all planes in an intraoperative dynamic range, which decreases postoperative complications. CONCLUSION: Conversion from hip fusion to THA is a rare and complex procedure. The use of DAA with a standard table and fluoroscopy helps to avoid high complications since it allows a dynamic intra-operative examination of the range of motion to rule out impingements, reduces the risk of dislocation, and allows leg lengthening verification.

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.

Hip arthrodesis in children : a review of 26 cases with a mean of 20 years' follow-up.

AIMS: To examine the long-term outcome of arthrodesis of the hip undertaken in a paediatric population in treating painful arthritis of the hip. In our patient population, most of whom live rurally in hilly terrain and have limited healthcare access and resources, hip arthrodesis has been an important surgical option for the monoarticular painful hip in a child. METHODS: A follow-up investigation was undertaken on a cohort of 28 children previously reported at a mean of 4.8 years. The present study looked at 26 patients who had an arthrodesis of the hip as a child at a mean follow-up of 20 years (15 to 29). RESULTS: The mean Harris Hip Score (HHS) increased from 39.60 (SD 11.06) preoperatively to 81.02 (SD 8.86; p = 0.041) at final review. At latest follow-up, the HHS was found to be excellent in four patients (15%), good in 11 (42%), and fair in 11 (42%). A total of 16 patients (62%) reported mild low back pain, five (19%) had moderate pain, and five (19%) patients had no back pain. Mild ipsilateral knee pain was reported by 19 (73%), moderate pain by one (4%), and no pain by six (23%) patients. Mild contralateral hip pain was reported by ten patients (38%), and no pain by 16 (62%). The 36-Item Short Form Health Survey scores were very good in four patients (15%), good in 18 (70%), and poor in four (15%), with a mean score of 70.92 (SD 12.65). Of 13 female patients who had given birth, 12 did so with uncomplicated vaginal delivery. All patients had to modify their posture for toileting, putting on lower body clothes, foot care, and putting on shoes. CONCLUSION: Our results show that with hip arthrodesis, most patients have relatively good function at long-term follow-up, although some pain is experienced in adjacent joints, and modification in some activities of daily living is common.Cite this article: Bone Joint J 2022;104-B(9):1089-1094.

Total Knee Arthroplasty in Patients With Prior Ipsilateral Hip Fusion: A Surgical Technique.

BACKGROUND: In patients with severe osteoarthritis of the knee with prior ipsilateral hip fusion who require total knee arthroplasty (TKA), a controversial issue is whether to first convert the hip fusion to a total hip arthroplasty (THA) or to perform TKA without reconstruction of the hip. Also, immobility of the ipsilateral, fused hip adds significant technical challenge because the usual positioning of the leg requires modification in order to gain access needed for the TKA. TECHNIQUE: In such cases, we position the patient with the knee suspended, similar to how we perform knee arthroscopy. In our experience, the ipsilateral knee has significant deformity and is best addressed with a constrained, hinged TKA. RESULTS: In 3 patients with severe knee osteoarthritis with prior ipsilateral hip fusion-a 72-year-old man and a 79-year-old woman with hip arthrodesis due to posttraumatic arthritis and an 81-year-old woman with hip arthrodesis due to congenital dislocation of the hip-rotating-hinge knee prostheses were implanted due to severe knee instability. All 3 patients had satisfactory results, without complications, after follow-up of 1 to 5 years. CONCLUSIONS: We obtained satisfactory results in the short and medium term without previously converting the hip arthrodesis to THA by positioning patients with the knee suspended, in a way similar to when knee arthroscopy is performed, and implanting rotating hinge TKAs due to severe preoperative knee instability.

Use of Imageless Navigation in the Conversion of Hip Fusion to Total Hip Arthroplasty.

Conversion of hip arthrodesis to total hip arthroplasty is associated with significant challenges, including accurate restoration of leg length and proper orientation of the acetabular component. Computer-assisted navigation provides real-time data on these parameters that may be a useful augment during hip fusion takedown surgery. Here, we present the case of a 64-year-old woman who presented with symptoms related to a left hip arthrodesis. The patient underwent a left-sided hip arthrodesis takedown and conversion to a total hip arthroplasty (THA). Due to the altered anatomical architecture of the fused hip, imageless navigation was used to assist with the conversion to THA. This case demonstrates that in complex hip arthroplasty procedures, where anatomical morphology is altered, navigation technology can be beneficial in addressing the challenges of achieving optimal placement of acetabular components and establishing appropriate leg length and offset.

Conversion of Hip Arthrodesis Using Robotic Arm Technology.

Recent advancements in computer-assisted surgery have led to a renewed interest in robotic-assisted hip arthroplasty. This technology assists with component position which is especially useful in prior trauma or dysplasia cases. We present a case of a surgical hip fusion conversion to total hip arthroplasty with the use of robotic-assisted technology. Enhanced preoperative planning with the ability to manipulate implant position before execution can be invaluable during complex procedures. Further research is warranted before revision cases using computerized navigation systems becomes more prevalent.

Robotic-Arm Assistance Simplifies Hip Arthrodesis Conversion to Total Hip Arthroplasty.

Hip fusion takedown to total hip replacement is a challenging operation. Neck osteotomy and acetabular component placement are technically demanding and often require fluoroscopic guidance. Robotic arm-assisted total hip arthroplasty enhances accuracy of preoperative planning and provides navigated guidance for neck osteotomy and haptic guidance on acetabular reaming and cup implantation. Fluoroscopic guidance is replaced by real-time navigation and on-screen data. This article describes how robotic arm assistance can simplify this complex operation.

Total Knee Arthroplasty with Prior Ipsilateral Hip Arthrodesis.

Total knee arthroplasty (TKA) in the setting of previous hip fusion is rare with a paucity of evidence in the orthopaedic literature. Traditionally, TKA is performed supine, with the aid of knee-positioning devices allowing for hip flexion and range of motion of the knee to facilitate ease of surgical intervention. However, TKA using traditional positioning would not be possible in the presence of ipsilateral hip arthrodesis preventing hip motion. This case report describes a TKA performed for a 72-year-old woman with end-stage osteoarthritis of the right knee, ipsilateral hip arthrodesis, and leg-length discrepancy as the sequelae of slipped capital femoral epiphysis. We describe novel surgical positioning to be used to facilitate TKA in the absence of ipsilateral hip motion with bed modifications and the use of an extremity positioning device.

Robot-Assisted Total Hip Arthroplasty for Arthrodesed Hips.

BACKGROUND: Conversion of arthrodesed hips to total hip arthroplasty (THA) remains technically demanding. This study aims to evaluate the safety and efficacy of robot-assisted THA in arthrodesed hips. METHODS: We retrospectively analyzed 45 ankylosing spondylitis patients with hip arthrodesis in the Chinese PLA General Hospital between August 2018 and August 2019. All surgeries were carried out by one single surgeon. The patients were followed at 3 months after surgery. Gender, body mass index, angle of hip arthrodesis, operating time, intraoperative fluoroscopic times, postoperative length of hospitalization, cup positioning, postoperative leg length discrepancy, offset discrepancy, intraoperative and postoperative complications, and postoperative Harris Hip Score were collected for all patients. RESULTS: Twenty-two patients (35 hips) who underwent robot-assisted THA and 23 patients (37 hips) who underwent manual THA were enrolled in this study. There were no significant differences in demographics and arthrodesed angles between the two groups. The fluoroscopic times during manual THA were significantly higher than those during robot-assisted THA (2.16±1.61 vs 0.47±0.61, respectively, p=0.000). In the robotic group, the percentage of acetabular cups within the safe zone was significantly greater than in the manual group (94.29% vs 67.56%, respectively, p=0.042). For manual THA, the anteversions were significantly different between the left and right sides (21.14±7.86 vs 16.00±6.32, respectively, p=0.042); however, no such significant difference was found in robot-assisted THA. CONCLUSION: Compared with manual THA for arthrodesed hips, robot-assisted THA had significant advantages in improving the frequency of achieving cup positioning within the target zone with diminished radiation dose and no increase in operating time.

Intertrochanteric Fracture in a Long-term Ankylosed Hip: A Case Report.

INTRODUCTION: The main objectives in the treatment of an intertrochanteric fracture in elderly population are to prevent medical complications, maintain mobility, independence, and relieve pain. When this fracture occurs in an arthrodesed hip, there is a significant lack of scientific evidence of optimal treatment and clinical results since only few case reports have been published so far. CASE REPORT: A Caucasian 83-year-old woman slipped and fell, complaining of the left hip pain. After radiographic evaluation, she was diagnosed with an intertrochanteric fracture that occurred in a long-term arthrodesed hip. We treated this rare presentation by open reduction and internal fixation with a proximal locking femoral plate and a pelvic reconstruction plate. No immobilization was needed in the post-operative care. Fracture healing occurred after 3months. CONCLUSION: Without motion on the hip, the lower extremity forms one long lever arm, creating an unusual instability at the fracture site. The authors decided that, to overcome this situation, the construction had to be reinforced and extended from the iliac wing to the proximal femur with two plates. This provided enough strength and stability to allow an uneventful fracture healing. This approach can be easily reproduced and can be considered in future similar patients.

Unusual presentation of recurrent subtrochanteric non-union in a patient with hip arthrodesis: A case report.

This case report describes the management and therapeutic solution for the treatment of subtrochanteric non-union in a patient with hip arthrodesis. Two techniques can be used in the treatment of these non-unions: a closed intramedullary nailing or an open technique with plate, preferably carried out together with cortical bone graft. The surgical technique varies depending on the fixation method used for the initial treatment of the fracture and on the characteristics of the non-union. We report an unusual case of a patient who started her long clinical history more than 40 years ago with a septic arthritis of the hip healed in arthrodesis. 35 years later, after having undergone various surgeries, she fractured the proximal femur, which had to be operated seven times before reaching healing. Satisfactory outcomes were finally obtained. Arthrodesis proved to be the main cause of failed healing and of the recurrent non-union.

Conversión de artrodesis a prótesis total de cadera en México. Reporte de un caso / Conversion of arthrodesis to total hip replacement in Mexico. Case report

Resumen: Desde 1900, la artrodesis de cadera se consideraba como un tratamiento definitivo, siendo el método de elección para la osteoartritis (OA) de cadera en pacientes jóvenes y otros padecimientos como infecciones o secuelas de enfermedades infantiles, aunque hoy día se ha migrado al uso de prótesis con implantes no cementados. Actualmente, el manejo ortopédico de la osteoartritis en la cadera del paciente joven ha cambiado de forma impresionante, en parte derivado de las consecuencias de la artrodesis a largo plazo en las articulaciones vecinas, por ello presentamos este caso en el que se realiza la conversión a una artroplastía total de cadera (ATC).

Abstract: Since 1900, hip fusion was considered a definitive treatment, being the method of choice for osteoarthritis (OA) of the hip in young patients, and others as infections or sequelae of childhood illnesses, although today it has been migrated to the use of prostheses with non-cemented implants. Currently orthopedic management of osteoarthritis in the hip of the young patient has changed dramatically in part derived from the consequences of long-term arthrodesis in adjacent joints, so we present this case where we perform the conversion to total hip arthroplasty.

Total hip arthroplasty following arthrodesis: a single-center experience of 17 patients.

PURPOSE: We aimed to present our experience with total hip arthroplasty in patients with previous hip arthrodesis. PATIENTS AND METHODS: This was a retrospective study, in which clinical and radiological outcomes of total hip arthroplasty performed in 17 patients (mean age 54.2±8.5 years; age range 33-68 years; female to male ratio 10/7) with previous arthrodesis in our clinic between 2001 and 2014 were reviewed. Patients were followed up for 6.7±2.8 years (range 3-12 years) after the operation and evaluated for ipsilateral knee pain, range of motion, walking capacity, and leg-length discrepancy. The clinical outcome was assessed by the Harris Hip Score. RESULTS: The outcome of arthroplasty was good or excellent in 14 of 17 patients (82.3%), fair in two patients (11.8%), and failure in one patient (5.9%). The Harris Hip Score increased to 79.8±9.8 postoperatively from a preoperative score of 40.9±10.1 (p<0.01). Pain-free hip was obtained in 15 patients (88.2%), and range of motion was 88°. Fourteen patients (82.4%) reported a significant decrease in back pain, and 11 patients (64.7%) in ipsilateral knee pain. Ten patients (58.8%) were able to walk normally, five patients (29.4%) walked with slight Trendelenburg gait without support, and two patients (11.8%) with severe Trendelenburg gait using arm rests. The mean leg-length discrepancy was 1.1 cm (range 0-3 cm). The complications were peroneal nerve palsy (n=3), superficial wound infection (n=3), hip dislocation (n=2), and heterotopic ossification (n=3). CONCLUSION: If it is well planned, conversion of hip arthrodesis to total hip arthroplasty is a successful and safe procedure, which increases patients' functionality.

Long-term results of custom cementless-stem total hip arthroplasty performed in hip fusion.

INTRODUCTION: Due to complex anatomical considerations, results of cementless-stem total hip arthroplasty (THA) in hip fusion remain controversial compared with conventional THA. We therefore aimed to analyse 3D anatomy of the fused hip based on pre-operative computed tomography (CT) scans, functional outcomes based on the Harris Hip Score (HHS) and the Hip Disability and Osteoarthritis Outcome Score (HOOS), modifications of hip anatomy based on post-operative standardised radiography, and determine complication rate and long-term survival based on Kaplan-Meier analysis. METHODS: We retrospectively studied 23 hips that underwent conversion of a fused hip to THA using a 3D CT scan-based custom titanium (Ti alloy hypoxyapetite (HA)-coated stem. The mean follow-up was 15 (9-22) years. Femur anteversion ranged from -29° to 80°. RESULTS: HHS improved from 59 to 89 points and average range of motion (ROM) was 88° for flexion. Back pain decreased in 62%, and knee pain decreased in 42%. The mean post-operative leg-length discrepancy was 7.8 mm. No intra-operative complications occurred. One aseptic stem loosening for mechanical failure was observed. The Kaplan-Meier survivorship considering revision for any reasons as the end point was 95.6% [95% confidence interval (CI) 92.4-98.8] at 15 years. CONCLUSION: Custom cementless stems may be an interesting solution to address the particular anatomical features of hip fusion at the time of THA, with an excellent survival rate at 15 years.

Total knee arthroplasty in patients with prior ipsilateral hip arthrodesis.

Only a few articles based on the management of symptomatic knee osteoarthritis in patients with prior ipsilateral hip arthrodesis have been reported, and there are no clear criteria for the best treatment option [to carry out a total knee arthroplasty (TKA)-or to take down the hip fusion and conversion to a total hip arthroplasty-THA, and after that to carry out the TKA]. We report two cases, a 72-year-old male who underwent a left hip arthrodesis at 28 because of a trauma and a 51-year-old woman who underwent a left hip arthrodesis at 9 years because of a congenital dislocation. They presented severe ipsilateral symptomatic knee osteoarthritis. Once the cases were studied and the two therapeutic possibilities were evaluated, we decided to perform TKA. Currently, both patients have no pain, a stable knee with good range of motion and without aseptic loosening radiologic criteria.

[Conversion of arthrodesis to total hip replacement in Mexico. Case report]. / Conversión de artrodesis a prótesis total de cadera en México. Reporte de un caso.

Since 1900, hip fusion was considered a definitive treatment, being the method of choice for osteoarthritis (OA) of the hip in young patients, and others as infections or sequelae of childhood illnesses, although today it has been migrated to the use of prostheses with non-cemented implants. Currently orthopedic management of osteoarthritis in the hip of the young patient has changed dramatically in part derived from the consequences of long-term arthrodesis in adjacent joints, so we present this case where we perform the conversion to total hip arthroplasty.

Desde 1900, la artrodesis de cadera se consideraba como un tratamiento definitivo, siendo el método de elección para la osteoartritis (OA) de cadera en pacientes jóvenes y otros padecimientos como infecciones o secuelas de enfermedades infantiles, aunque hoy día se ha migrado al uso de prótesis con implantes no cementados. Actualmente, el manejo ortopédico de la osteoartritis en la cadera del paciente joven ha cambiado de forma impresionante, en parte derivado de las consecuencias de la artrodesis a largo plazo en las articulaciones vecinas, por ello presentamos este caso en el que se realiza la conversión a una artroplastía total de cadera (ATC).

Hip fusion takedown to a total hip arthroplasty-is it worth it? A systematic review.

INTRODUCTION: Patients with surgically or spontaneously fused hips are often dissatisfied with their overall function and the debilitating effect on adjacent joints. Therefore, in properly selected patients, hip fusion-takedown and conversion to total hip arthroplasty (THA) can result in improved function and decreased pain. We aimed to (1) evaluate the indications for conversion, (2) evaluate the clinical outcomes, (3) analyze the overall complications, and (4) identify the overall satisfaction following the procedure. METHODS: A systematic and comprehensive literature search was performed to analyze studies evaluating conversion of hip fusion to THA. After reviewing 3,882 studies, 27 total studies (1,104 hips) met our inclusion/exclusion criteria and were included in our final analysis. A weighted mean of rates was determined for each complication, including infection, instability, loosening, nerve-related, abductor-related, venous thrombotic event, and revision. RESULTS: The study population consisted of 53.2% male and 46.8% female subjects. The mean age at time of conversion was 52 years (range 36-65 years), the mean time until follow-up was 9.2 years (range 2.5-17.3), and the mean duration of arthrodesis was 27.7 years (range 11-40.2). As measured by Harris Hip Score, overall clinical outcomes improved from 58.1 points (range 42.4-70 points) pre-operatively to 80.0 (range 62-93.5) post-operatively. The specific complication rates were 5.3% (range 0-43.6%) for infection, 2.6% (range 0-15.4%) for instability, 6.2% (range 0-17.2%) for loosening, 4.7% (range 0-13%) for nerve-related complications, 13.1% (range 0-87%) for abductor-related complications, and 1.2% (range 0-13%) for venous thrombotic events. The revision rate was 12.0% (range 0-43.6%). CONCLUSION: Takedown of a fused-hip can be a challenging procedure. Although patients can benefit functionally, both patients and surgeons need to be aware of the complications and increased risk of further revision procedures, which should be an important part of the pre-operative discussion.

Conversion of hip fusion to total hip arthroplasty: clinical, radiological outcomes and complications in 40 hips.

OBJECTIVE: The purpose of this retrospective study is to report the clinical and radiological outcome of total hip arthroplasty in patients with previous hip arthrodesis. PATIENTS AND METHODS: We retrospectively reviewed 28 (40 hips) prospectively followed patients in whom ankylosed hips were converted to total hip arthroplasty (THA) between 2010 and 2014 in our institution. The average age at the time of the conversion operation was 40.8 ± 9.8 years (range 24-62). The ankylosis had lasted 20.4 ± 13.0 years (range 3-56) before conversion surgery. The etiology of the ankylosis was septic arthritis in 10 (25%), post-traumatic hip osteoarthritis in 8 (20%), developmental hip dysplasia in 6 (15%), rheumatoid arthritis in 6 (15%), primary osteoarthritis in 5 (12.5%) and ankylosing spondylitis in 5 (12.5%) hips. The indications for arthroplasty were intractable low back pain in 14 (50%), hip pain in 24 (85.7%), and ipsilateral knee pain in 19 (67.8%) patients. Harris Hip Score (HHS) was used to rate the clinical results before and after the surgery. Radiographic evaluations included component malposition and loosening. All complications during the study period were recorded. RESULTS: The mean follow-up period was 39.9 ± 10.6 months (range 24-60). The mean preoperative HHS was 33.3 ± 8.6 (range 18-50) and the mean HHS at the final follow-up was 74.9 ± 8.6 (range 52-97). There was a statistically significant increase in HHS (p = 0.0001). HHS was excellent in 1, good in 6, fair in 14 and poor in 7 patients. Increase in HHS was lower than 20 points in one patient (18 points), and one patient required two-staged exchange procedure due to deep infection. Thus, according to our success criteria (increase in HHS more than 20 points, radiographically stable implant, and no further surgical reconstruction), 92.8% (26/28) of patients had benefit from the surgery. Trendelenburg sign was positive in 12 hips. There was limb length inequality in 11 patients (mean 0.5 cm, range 1-3 cm). No patients had heterotopic ossification, sciatic nerve palsy or dislocation. There were five intra-operative fractures of the greater trochanter that were treated with cable wiring. One patient had trochanteric avulsion injury and was treated with trochanteric grip and cables. One patient (2.5%) had deep infection one year after the conversion THA and was treated with two-staged exchange procedure. CONCLUSION: Conversion hip arthroplasty is an effective treatment method which provides functional recovery and patient satisfaction. However, a proper surgical technique and planning is necessary to minimize the complications.

Two-stage total hip arthroplasty for complex pelvic abnormalities: Example of hip arthrodesis conversion with concomitant treatment of pelvic and acetabular non-union.

Hip prosthesis implantation requires a stable pelvic foundation, which may be lacking in patients with complex pelvic abnormalities (e.g., arthrodesis conversion, tumour excision, or revision with large bony defects). Many reconstructive options exist for these situations, but their outcomes vary with the initial amount of bone loss and with the technique used. We describe a two-stage arthroplasty technique (acetabular cup first, then femoral stem) and report its use in a case of arthrodesis conversion with concomitant treatment of pelvic and acetabular non-union. Clinical and radiological outcomes after 5 years are reported. This procedure can be adapted to the most complex cases of pelvic reconstruction.

Anterior approach for total hip arthroplasty conversion of hip fusion.

PURPOSE: Hip fusion conversion has shown mixed results, in particular a higher rate of failure than primary total hip replacement. Conversion is usually carried out by a lateral approach. METHODS: We reported a series of 37 hip fusion conversions performed by an anterior approach. Clinical and radiographic outcomes of this unusual approach were reported at eight years of follow up. RESULTS: At eight years of follow up, survivorship was 86. 6 % (IC 95 %: 62.4-95.7 %). Sixteen patients reported good relief of the pre-operative back spine or knee pain. PMA score was significantly improved. Two implant aseptic loosenings needing revision surgery were reported. CONCLUSION: The anterior approach seemed to be as good as the other hip approaches for hip fusion conversion to total hip replacement.