To determine the major risk factors for unplanned reoperations (UROs) following corrective surgery for adult spinal deformity (ASD) and their interactions, using machine learning-based prediction algorithms and game theory. Patients who underwent surgery for ASD, with a minimum of two-year follow-up, were retrospectively reviewed. In total, 210 patients were included and randomly allocated into training (70% of the sample size) and test (the remaining 30%) sets to develop the machine learning algorithm. Risk factors were included in the analysis, along with clinical characteristics and parameters acquired through diagnostic radiology.Aims
Methods
The incidence of atypical femoral fractures (AFFs) continues to increase. However, there are currently few long-term studies on the complications of AFFs and factors affecting them. Therefore, we attempted to investigate the outcomes, complications, and risk factors for complication through mid-term follow-up of more than three years. From January 2003 to January 2016, 305 patients who underwent surgery for AFFs at six hospitals were enrolled. After exclusion, a total of 147 patients were included with a mean age of 71.6 years (48 to 89) and 146 of whom were female. We retrospectively evaluated medical records, and reviewed radiographs to investigate the fracture site, femur bowing angle, presence of delayed union or nonunion, contralateral AFFs, and peri-implant fracture. A statistical analysis was performed to identify the significance of associated factors.Aims
Methods
Load transfer to the bone is believed to be more physiological around the short stem in total hip arthroplasty (THA). However, we found unusual bony remodeling around the shortened tapered femoral stem. Among 121 consecutive THA using the same shortened tapered stem, 25 hips were excluded because the lateral cortex was already disturbed by previous surgery on the proximal femur. Sixteen hips were also excluded either because direct measurement was unavailable due to improperly taken final radiographs (n=9) or the patient was lost to follow-up (n=7).80 THAs were finally enrolled. Radiographic measurements were made using anteroposterior (AP) radiographs taken immediately and at 2 years after surgery. The thickness of the lateral cortex at the level of the distal end of the coated surface and at 10, 20, 30, and 40 mm proximal to it were measured. Variables for detecting the causative factors were age, gender, BMI, proximal femoral geometry, whether the surgery was done to dominant side, diagnosis leading to surgery, size and offset of the stem, articulation, alignments and operative time.Background
Methods
This study was performed to evaluate clinical and radiographic outcomes of Hip Resurfacing Arthroplasty for treatment of haemophilic hip arthropathy. Between 2002 and 2013, 17 cases of hip resurfacing arthroplasties were performed in 16 haemophilic patients (13 cases of haemophilia A, 2 cases of haemophilia B, 2 cases of von Willebrand disease). The average age of the patients was 32.5(range: 18∼52) years. The average follow up period from the operation was 6.3 (range: 2∼13) years. In this study, the subjects that completed follow-up were composed of 5 cases composed of patients who were treated with Conserve plus® hip resurfacing system, 5 cases composed of patients who were treated with Durom® hip resurfacing system, 4 cases who were treated with ASR® hip resurfacing system, and 3 cases who were treated with Birmingham® hip resurfacing system. The Modified Harris hip score, the range of motion of the hip joint, perioperative coagulation factor requirements and complications associated with bleeding were evaluated as part of the clinical assessment. For the radiographic assessment, fixation of component, presence of femoral neck fracture, osteolysis, loosening and other complications were evaluated.Purpose
Material & Method
The purpose of this study was to evaluate and compare the clinical, radiological outcomes of the group of patients with distal femoral cortical hypertrophy (DFCH) and without DFCH after hip arthroplasty using a cementless double tapered femoral stem and to analyze a correlation between patients factors and DFCH. Four hundreds four patients (437 hips) who underwent total hip arthroplasty (n = 293) or hemiarthroplasty (n = 144) using a Accolade TMZF femoral stem between Jun 2006 and March 2012 and were follow up period more than 24 months after surgery were enrolled in this study. They were divided into 2 groups, the one group (n = 27) included patients with DFCH, and the other group (n = 410) included patients without DFCH. The mean follow up period was 54.5 months (range, 24 to 85 months) and 56.2 months (range, 24 to 92 months) for patients with DFCH and without DFCH.Purpose
Materials and Methods
We performed this study to evaluate the clinical and radiological results of metal on metal articulation change for the treatment of ceramic liner or head fractures in total hip arthroplasty (THA). We retrospectively reviewed 8 patients with revision THA using liner cementation (metal on metal) due to ceramic fracture (liner fracture; 5 cases, head fracture; 3 cases). They were followed up for an average of 30 months (range 12 to 68 months). At the surgery, we removed ceramic liner and head, the joint cavity was irrigated with saline to remove remnants of ceramic particles. After that, the inner surface of the metal shell was roughened with a high-speed diamond burr to improve the fixation strength of the liner. Metal inlay polyethylene (Metasul®, Centerpulse Orthopedics, Austin, TX) liner was used and the back surface of the liner was routinely down sized and roughened like spider web with an electrical burr to ensure stable fixation with bone cement. We evaluated clinical result using Harris Hip Score (HSS) and the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) score and radiological evaluation was done using the mothod of DeLee and Charnley for the acetabular osteolysis and method of Gruen et al. for the femoral osteolysis. The mean Harris hip scores improved from 65.3 pre-operatively to 93.8 at the final follow-up. There were no changes in cup position, no progression of osteolytic lesion around the femoral and acetabular components and no measurable wear of metal on metal bearing articulation at the last follow-up radiographs. There was one case of recurrent dislocation after surgery and the patient treated with greater trochanter distal advancement. This study showed that for the treatment of ceramic liner or head fractures, after thorough removal of ceramic particles, cementation into a metal shell and changing the articulation to metal-on-metal provided good clinical and radiological results.
We wanted to evaluate the clinical and radiological results of acetabular revision using the acetabular reinforcement ring and allograft impaction in patients with severe acetabular bony defect. 41 hips revision arthroplasty using reinforcement ring were performed between April 1997 and October 2005 and were followed up for more than two years. The cause of primary arthroplasty was AVN in 18 cases, secondary osteoarthritis (OA) in 17 cases, fracture in cases and primary OA in 1 case. The cause of revision arthroplasty was acetabular cup loosening in 20 cases, massive osteolysis in 14 cases, infection in 4 cases, liner dissociation in 2 cases, and recurrent dislocation in 1 case. The average period between primary and revision arthroplasty was 11.4 years (range 0.6 to 29.1 years). Acetabular defects were classified based on the AAOS classification and Paprosky classification system. All were treated with autografts or allografts. Muller ring was used in 18 cases, Burch-Schneider ring was used in 14 cases, and Ganz ring in 9 cases. Clinical evaluations were performed according to the Harris hip score (HHS), and the radiographic results were evaluated by progression of acetabular component loosening, union of bone grafts, periacetabular osteolysis, and migration of the hip center. The mean preoperative Harris hip score of 64.9 was improved to 91.8 points at the latest follow-up. There were 39 cases of type 3 defect, 2 cases of type 4 defect according to the AAOS classification and 8 cases of type 2B defect, 3 cases of type 2C defect, 28 cases of type 3A defect, and 2 cases of type 3B defect according to Paprosky classification. Radiographically, the bone grafts were well united except one case. The mean preoperative hip center of rotation which was vertically 32.3mm, horizontally 33.2 mm migrated to vertically 26 mm, horizontally 33.2 mm postoperatively and it was statistically significant. The mean preoperative abductor lever arm of 41.7 mm changed to 45 mm postoperatively which was statistically insignificant. However the mean preoperatiave body lever arm of 89.4 mm changed to 96.9 mm postoperatively which was statistically significant. Postoperative complications were cup loosening in 1 case, dislocation in 2 cases, and recurrence of deep infection in 1 case. Clinically and radiographically, acetabular reconstruction using reinforcement ring showed very promising short term result. We conclude that reinforcement ring can provide stable support for grafted bone in severe bone defect. But meticulous surgical technique to get initial firm stability of ring and optimal indication in mandactory for the successful result.
The aim of the present study was to report the midterm follow up results of second generation metal-on-metal cementless total hip arthroplasties in patients younger than 50 years. From December 1997 and January 2003, 91 metal-on-metal cementless primary total arthroplasties in 77 patients (who were younger than 50 years) were performed in our institution. Among them 72 hips in 63 patients could be followed more than 5 years. There were 18 women (22 hips) and 44 men (50 hips) with a mean age at surgery of 39 years (range 22 to 49 years) and a mean follow up of 7 years (range 5 to 10 years). The most common cause of total hip replacement were avascular necrosis of femoral head (37 hips in 28 patients, 51%) and second one was osteoarthritis (13 hips in 13 patients, 18%). We used Fitmore (Zimmer, Winterthur, Switzerland) cup in all cases and used 28mm Metasul femoral head. About the femoral stem, CLS (Protek AG/Zimmer, Bern, Switzerland) stems were used in 48 hips and Cone prosthesis® (Protek AG, Berne, Switzerland) were used in 24 hips. We evaluated clinical result using Harris hip score (HSS) and the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) score and radiological evaluation was done using the method of DeLee and Charnley for the acetabular osteolysis and method of Gruen et al. for the femoral osteolysis. The mean HSS improved from 58.9 (range 35 to 69) preoperatively to 92.2 (range 82 to 100) postoperatively. The mean WOMAC score improved from 72.2 (range 63 to 94) preoperatively to 29.2 (range 17 to 51) postoperatively. In radiological evaluation, all femoral and acetabular component were well fixed without loosening or subsidence. But osteolysis was observed in 10 (14%) of total 72 hips (Acetabular osteolysis in 5 cases-Zone 2; 2, Zone 3; 3, Femoral osteolysis in 6 cases-Zone 1; 6, Zone 7; 1). About the major complications, there were immediate postoperative deep infection 1 case, delayed infection 1 case and recurrent dislocation 1 case. There was no revision case due to aseptic loosening. The treatment of second generation metal-on-metal cementless total hip arthroplasties in patients younger than 50 years showed favorable midterm results.
Reconstructive acetabular osteotomy is a well established and effective procedure in the treatment of acetabular dysplasia. However, the dysplasia is frequently accompanied by intra-articular pathology such as labral tears. We intended to determine whether a concomitant hip arthroscopy with peri-acetabular rotational osteotomy could identify and treat intra-articular pathology associated with dysplasia and thereby produce a favourable outcome. We prospectively evaluated 43 consecutive hips treated by combined arthroscopy and acetabular osteotomy. Intra-operative arthroscopic examination revealed labral lesions in 38 hips. At a mean follow-up of 74 months (60 to 97) the mean Harris hip score improved from 72.4 to 94.0 (p < 0.001), as did all the radiological parameters (p < 0.001). Complications included penetration of the joint by the osteotome in one patient, a fracture of the posterior column in another and deep-vein thrombosis in one further patient. This combined surgical treatment gave good results in the medium term. We suggest that arthroscopy of the hip can be performed in conjunction with peri-acetabular osteotomy to provide good results in patients with symptomatic dysplasia of the hip, and the arthroscopic treatment of intra-articular pathology may alter the progression of osteoarthritis.
The exact alignment of the femoral component is crucial for the success of hip resurfacing arthroplasty. This prospective study was performed to find whether the imageless computer-assisted navigation surgery can improve the accuracy during hip resurfacing arthroplasty by comparing the alignment of the femoral component implanted with navigation system and conventional-mechanical guided system. Forty patients were randomly allocated into 2 groups for resurfacing hip arthroplasty using Birmingham hip resurfacing system. In the conventional group, femoral component positioning was assisted by mechanical alignment guides. In the navigation group, it was assisted by an imageless computer-assisted surgical system of Vectorvision® (BrainLAB, Germany). We measured the difference between the preoperative plan of femoral component’s position and postoperative results on radiographs in the 2 groups In the conventional group, a median difference of the stem alignment was 5.4° (range, 0.2°–10.9°) and a median difference of the stem anteversion was 2.6° (range, 0°–6.5°). In the navigated group, a median difference of the stem alignment was 2.3° (range, 0.2°–4.9°) and a median difference of the stem anteversion was 1° (range, 0°–3.6°). These differences between the 2 groups were statistically significant (P<
0.05). In resurfacing arthroplasty with a hip navigation, the procedure showed a good performance and reliability. It is achieved with greater precision with a navigation system than a mechanical alignment system.
The ultimate goal for treatment of osteonecrosis of femoral head (ONFH) is preserving the femoral head. We have tried to manage the patient who received failed joint preserving procedures with resurfacing arthroplasty if they fit the indicati385on. In this brief review, we wanted to clarify the role and technical concern of resurfacing arthroplasty as a salvage procedure after failed joint preserving operations for ONFH. Among 556 hips underwent resurfacing arthroplasty from September 1998 to October 2007, sixteen resurfacing arthroplasties (13 patients) were performed after failed joint preserving procedures for ONFH. Mean age at the operation was 39 years old. Seven vascularized fibular grafts, 3 multiple drillings, 3 core decompressions and 3 combined procedures were performed as initial operations. Mean duration from the index operation and resurfacing was 95 months. Mean follow up was 14 months. The patients were clinically evaluated with the Harris hip score, hip or thigh pain, and range of motion. As a radiological evaluation, we measured positions of the acetabular cup and femoral stem, radiographic changes at the neck and complications. The Harris hip score increased from 69.2 preoperatively to 89.5 at the final visit. Hip range of motions other than sagittal directions significantly improved after the operation. No patient complained of limb length discrepancy. One patient complained of unexplained hip pain, and another patient had trochanteric pain. Other than those two cases, all patients regained their pre-morbid activity level uneventfully. Radiologically, eleven femoral stems in anteroposteior and lateral radiographs were exactly aligned along the previous operative tracts. However, there were no clinical complications related to the position of femoral component. The only case that the acetabular cup was implanted in high inclination (60 degrees) experienced sustained unexplained hip pain. There was no another complications. Our experience suggests that even for the case of failed hip preserving procedures in ONFH, resurfacing arthroplasty can play a successful role as a salvage operation. Furthermore, this can be an excellent alternative between joint preserving procedures and conventional THA.
The purpose of this study is to evaluate short to mid-term clinical and radiological results of metal on metal resurfacing arthroplasty in osteonecrosis of the femoral head (ONFH). 185 hips of 169 patients who underwent metal on metal resurfacing arthroplasty using Birmingham Hip Resurfacing system (Midland Medical Technololgies, Birmingham, UK) between December 1998 and May 2005 were available for this study and all cases were followed up over 3 years. All preoperative diagnoses were ONFH. The extents of necrotic area were analyzed by preoperative MRI scanning. Their mean age at the time of operation was 37.7(range, 16–67) years old and mean period of follow-up was 88(range, 36–113) months. For the clinical assessments, Harris hip scores, UCLA activity scores, pain and ROM were evaluated. Radiological changes such as radiolucencies around the stem, impingement sign, neck narrowing, osteolysis around head and neck junction, loosening of implants, heterotopic ossifications were evaluated in the serial antero-posterior, translateral radiographs of the hip joint. Preoperative necrotic area was average 42.7(range, 11.5–60) %. Clinically, the average Harris hip score was improved from 85.2 points to 97.1 points at final follow-up. Average UCLA activity scores at the last follow-up was 8.8 and almost of the patients showed high activity and returned to their original job. ROM were very satisfactory. Radiologically, the mean inclination of acetabular component was 48.0°. There were no radiolucent lines around the acetabular components, but 3 cases showed radiolucent lines around the stem of femoral components. Osteolytic lesions were noticed in 10 cases around head-neck junction. Nine hips had impingement signs around the head-neck junction. There was no case which showed evidence of stress shielding. Moderate neck narrowing were shown in 3 cases. There were 6 cases of heterotopic ossification. One hip had a revision surgery to a total hip arthroplasty using big metal ball because of loosening of acetabular component. There was no patient complained limb length discrepancy and no infection, dislocation, thigh pain. The midterm performance of metal on metal resurfacing arthroplasty in ONFH was very excellent in the aspects of pain relief, ROM of hip joints, rehabilitation and return to preoperative activity and minimization of common complications of conventional total hip arthroplasty. There was no mechanical failure related to the osteonecrosis and we can conclude that performing resurfacing arthorplasty in osteonecrosis less than 50% of extent can be justified. However, performing resurfacing arthroplasties in osteonecrosis of femoral heads needs meticulous surgical techniques and longer learning curve to prevent early failure. Even though our midterm follow-up study revealed excellent results, more long-term follow-up studies are mandatory to determine the survivorship and to verify the problems related to the increased serum metal ion and metal ion toxicity after resurfacing arthroplasty.
The purpose of this study is to analyze clinical and radiological results of total hip arthroplasty using the 3rd generation ceramic on ceramic articular surface. Between July 1999 and May 2005, 339 hips of 250 patients had primary cementless total hip arthroplasty with the 3rd generation ceramic on ceramic bearing implants. And 325 hips of 236 patients were followed up over 3 years. Male were 168 patients(237 hips) and female were 68 patients(88 hips). The mean age at the time of operation was 47.3(range, 25~76) years old and the mean follow up period was 62.4(range, 36~107.6) months. The preoperative diagnoses were osteonecrosis of the femoral head (ONFH) in 250 hips, secondary osteoarthritis in 55 hips(dysplasia in 35, infection sequalae in 12, LCP in 2, CDH in 2), hemophilic arthropathy in 9 hips, ankylosing spondylitis in 7 hips etc. We used Bicontact system(Aesculap, Germany) in 65 hips, Secur-FitTM(Stryker Howmedica Osteonics, USA) in 206 hips, Trilogy ABTM (Zimmer, USA) in 54 hips. Clinically, Harris Hip Score, thigh pain, squeaking and other complications were evaluated. Radiologically, the serial radiographs were analyzed. Clinically, the Harris hip score was improved from preoperative 66.0(19~91) to 96.2(58~100) at the last follow-up. Radiologically, there was no loosening of implants and visible wear and osteolysis. Heterotopic ossifications were noted in 5 cases. In complications, there was dislocation in one case, periprosthetic fracture in 2 cases and thigh pain in 9 cases. Intermittent squeaking sound has occurred in 8 cases(2.5%). Among these, one case of loud squeaking which happened after fall down had revision surgery. There was no infection and fracture of ceramic implant. Our midterm results of THA with the 3rd generation ceramic bearing system were very satisfactory and demonstrated that the 3rd generation ceramic bearings remain as an excellent bearing choice because of their superior wear characteristics. However, the results of this study suggests that the squeaking would be one of strong potential risk factors for failure of ceramic on ceramic total hip arthroplasty and we must be very cautious to prevent squeaking.
The aim of this study is to analyse the mid to long term results of cementless total hip arthroplasty (THA) performed in hemophilic coxarthrosis. Twenty-seven consecutive cementless THAs (23 patients) were performed at our institute for hemophilic coxarthrosis between June 1995 and June 2003. All these patients were followed up regularly for minimum 5 years and were included in this study. The average age at the time of surgery was 36 years (± 8.1) (range, 24–52 years). All the patients had hemophilia A. Twelve patients (52%) had more than 1 joint affected by hemophilic arthropathy. The mean follow-up period was 92 months (± 31.4) (range, 60–156 months). For clinical assessment we evaluated Harris hip score, range of motion, amount of transfusion and factor replacement, perioperative bleeding and the problems associated with the use of coagulation factors. For radiographic assessment, we evaluated the stability and fixation of components, various bone responses around the implants and complications such as loosening and osteolysis. The average Harris hip score improved from 60.7 (± 19.3) (range, 30–89) before surgery to 95.9 (± 3) (range, 90–100) at the latest follow-up. The hip range of motion increased in all planes of motion after the operation. The mean factor VIII requirement per THA was 37 500 units (± 18 500) (range, 19 000–90 000 units). During surgery and post operative period mean 1.5 units (± 1.5) (range, 0–5 units) of packed cells and 0.5 units (± 1.4) (range, 0–5 units) of fresh frozen plasma was required. There was episode of re-bleeding in 4 cases. In one of them, severe osteolysis around pelvis and femoral stem was noted due to pseudotumor. Radiographically, except 1 loosened cup, the fixation was stable in all cases at the latest follow-up. Heterotopic ossification was noted in 2 hips. Osteolysis was noted in 4 femurs and 5 acetabulae. In 1 case of severe osteolysis around the stem, morsellised bone graft was performed at 144 months after the index operation. One case of pseudotumor was waiting for surgery. One loosened cup was revised to a cemented cup. Unlike worrisome results of cemented THA, meticulously performed cementless THA for moderate or severe hemophilic arthropathy is safe and greatly effective in reducing pain, increasing the range of motion and improving the walking ability. However, special attention must be paid to the possible complications associated with re-bleeding such as pseudotumor around the hip. To obtain the best results multidisciplinary team comprising of pediatrician, hematologist, rehabilitation therapist and orthopaedic surgeon should be needed.
We performed 52 total hip replacements in 52 patients using a cementless acetabular component combined with a circumferential osteotomy of the medial acetabular wall for the late sequelae of childhood septic arthritis of the hip. The mean age of the patients at operation was 44.5 years (22 to 66) and the mean follow-up was 7.8 years (5 to 11.8). The mean improvement in the Harris Hip Score was 29.6 points (19 to 51) at final follow-up. The mean cover of the acetabular component was 98.5% (87.8% to 100%). The medial acetabular wall was preserved with a mean thickness of 8.3 mm (1.7 to 17.4) and the mean length of abductor lever arm increased from 43.4 mm (19.1 to 62) to 54.2 mm (36.5 to 68.6). One acetabular component was revised for loosening and osteolysis 4.5 years postoperatively, and one had radiolucent lines in all acetabular zones at final review. Kaplan-Meier survival was 94.2% (95% confidence interval 85.8% to 100%) at 7.3 years, with revision or radiological loosening as an end-point when two hips were at risk. A cementless acetabular component combined with circumferential medial acetabular wall osteotomy provides favourable results for acetabular reconstruction in patients who present with late sequelae of childhood septic hip arthritis.
The congenital or acquired contracture of gluteus maximus is relatively rare, and its clinical feature of chronic lower back pain and extension contracture of the hip joint had been confused with herniations of lumbar disc disease or sequelae of cerebral palsy. The authors successfully treated these contracture of gluteus maximus, so report these cases and results. 9 patients suffering from Difficulty in squatting position or gait disturbance were surgically treated in our department from 1979 to 2000. There were eight men and a woman, mean age was 17.3 years old, and seven patients were bilateral. Four patients revealed past medical history of multiple intramuscular injection at gluteal region, but five patients revealed unremarkable history. Preoperative mean further flexion, internal rotation and external rotation of hip joint were 42°, 15°, and −5°. These patients revealed specific features of frog leg position in squatting position. Intraoperatively, the authors released the fibrotic band of the gluteus maximus, the short external rotators, the gluteal attachment of the iliotibial band and the joint capsule. After anesthesiologic recovery, active and passive joint motion exercise of flexion and rotation was started to prevent recurrence of contracture. Postoperatively, mean further flexion of hip joint were increased to 105°, and no Difficulty in sitting or squatting position, but slight limitation in rotation was remained. In follow up visit, no decrease of articular motion were observed. Conclusively, severe limitation of joint motion due to contracture of gluteus maximus can be successfully treated with surgical maneuver accompanied with postoperative aggressive physical therapy.
