Il-Yong Choi

Cementless Total Hip Arthroplasty With a Metal-on-Metal Bearing in Patients Younger Than 50 Years

Total hip arthroplasty (THA) longevity is the primary concern in young patients. Metal-on-metal articulations were reintroduced to reduce polyethylene particle-induced osteolysis and improve survivorship; to date, based on issued reports, this strategy appears to have been successful. In this study, the authors investigated metal-on-metal articulation survivorship and osteolysis incidence in young patients (19-50 years old at index operations) and retrospectively reviewed cementless metal-on-metal THAs in 70 patients (78 hips) with a mean follow-up of 12.4 years. Metasul articulation was used with the Wagner acetabular component in all. Survivorship with revision for any cause was 98.7% (95% confidence interval, 98%-100%), and survivorship due to the development of osteolysis for any lesion was 97.5% (95% confidence interval, 95%-99%). Mean Harris hip score improved from 51 to 95 points at final follow-up. The findings of this study indicate that outcomes of cementless THA with a metal-on-metal bearing in young patients are satisfactory. However, longer-term studies in larger cohorts are required to determine whether metal-on-metal articulations are really a favorable option in young patients.

Prophylaxis for deep vein thrombosis with aspirin or low molecular weight dextran in Korean patients undergoing total hip replacement;a randomized controlled trial

Summary. 150 Korean patients undergoing primary uncemented total hip replacement were randomized into 3 treatment groups for deep vein thrombosis (DVT) prophylaxis. Group A(50) were controls; Group B(50) received aspirin 1.2 g daily in 3 divided doses from 2 days before, to 14 days after surgery; Group C(50), received low molecular weight dextran 500 ml, infused intravenously at 50 ml/hour during surgery, and on each of the following 2 days. Contrast venograms were performed prior to surgery and 7 – 10 days after. The incidence of DVT was 20% in the control group, 12% in the aspirin group (p <0.1 vs control), and 6% in the dextran group (p <0.05 vs control). In patients developing DVT, the ratio of proximal to distal thrombi was increased in the control group as compared to treated groups (4 : 1 in the control group vs 1.5 : 1 in the treated groups). Both aspirin and dextran were well tolerated. Obesity (p <0.05) and long-term administration of steroids (p <0.05) were risk factors for deep vein thrombosis which reached statistical significance in the control group. Intraoperative venograms performed on 10 patients, showed that hip flexion (mean 40.4°) plus adduction (mean 11.5°) plus internal rotation (mean 81.5°), resulted in severe twisting or kinking of the femoral vein with stagnation of blood flow. Low molecular weight dextran significantly reduce the incidence of deep venous thrombosis and aspirin, though less effective, had a similar effect. Internal rotation of the hip joint should be minimized during operation in order to limit stagnation of blood flow in the femoral vein.Résumé. 150 patients coréens operes pour un remplacement total de hanche non-cimentée ont été triés au hasard en 3 groupes de traitement de prophylaxie de la thrombose. Le groupe A(50): groupe de contrôle. Le groupe B a reçu 1.2 g d’aspirine par jour en 3 doses à compter de 2 jours avant l’opération jusqu’à 14 jours après celle-ci. Le groupe C(50) a reçu des petites molécules de dextrane 500 ml par injection intraveineuse de 50 ml/heure pendant l’intervention et durant les 2 jours suivants. Une phlébographie de contrôle a été rèalisé avant l’intervention et 7 – 10 jours après celle-ci. Le taux de thrombose veineuse profonde (TVP) était de 20% dans le groupe du contrôle, 12% dans le groupe «aspirine» (p <0.1 contre contrôle) et 6% dans le groupe de «dextrane» (p <0.05 contre contrôle). Parmi les patients développant une TVP, le ratio proximal/distal était cliniquement augmenté dans le groupe du contrôle comparé avec les groupes traités (4 : 1 dans le groupe du contrôle contre 1.5 : 1 dans les groupes traités). L’aspirine et la dextrane ont bien été tolerées. L’obésité (p <0.05) et l’administration à long-terme de stéroïde étaient des facteurs de risque pour la TVP avec une signification statistique dans le groupe du contrôle. Les phlébographies per-operatoires faites chez 10 patients ont montré que la flexion (moyenne 40.4°) plus l’adduction (moyenne 11.5°) plus la rotation interne (moyenne 81.5°) se sont traduites par une grave torsion de la veine fémorale accompagné d’une stagnation circulatoire. Les petites molécules de dextrane réduisent significativement le taux de trombose veineuse chez les patients coréens qui ont subi une intervention chirurgicale de remplacement de la hanche et l’aspirine, quoique moins efficace, réduit aussi le taux de TVP. Pour limiter la stagnation de la circulation du sang dans la veine fémorale pendant l’intervention chirurgicale, la rotation interne de la hanche doit être minimisée.

Total hip arthroplasty using cementless grit-blasted femoral component: a minimum 10-year follow-up study.

The grit-blasted cementless Spotorno (CLS) stem, which has excellent survival rates up to 10 years, is widely used in total hip arthroplasty (THA). We investigated the survivorships of CLS stems in THA at a minimum follow-up of 10 years and sought to identify factors that influence outcomes. A total of 227 hips of 191 patients who underwent cementless THA with a CLS stem were retrospectively reviewed at a mean follow-up of 12.3 years. All patients were evaluated clinically and radiographically according to implant type and surgery-related and patient-related factors. Survivorship was 97.2% when femoral revision for any reason was defined as the end point. Femoral revisions were performed in 3 hips because of periprosthetic fractures. Survivorship for all hips, using revision for any reason as the end point, was 92.6%. Two metal-on-metal THAs were revised because of aseptic loosening or osteolysis around the cup. No significant differences were evident for type of stem, type of bearing surface, stem alignment, or patient-related factors. However, a canal fill index of 80% or less was found to affect cortical remodeling, subsidence, and a change in stem position of 5° or more, which indicates that care must be taken not to undersize stems. In addition, in view of the revisions performed, bearing surfaces appear to importantly influence THA survivorship.

Is second generation metal-on-metal primary total hip arthroplasty with a 28 mm head a worthy option?: a 12- to 18-year follow-up study.

To determine whether MoM THA with a small head is still worthy of use, we investigated survivorship, complications, and factors influencing failure. Of 149 consecutive patients (195 hips), 141 (180 hips) of mean age 43 (19-55) years were available for review at a mean of 14.4 years postoperatively. Survivorship for cup revision for any cause was 97.8% at 18.4 years postoperatively. Nine hips generated complaints of groin pain; six showed periacetabular osteolysis, one had pain without radiological change, and two were diagnosed as symptomatic pseudotumors. Four of six hips with periacetabular osteolysis or aseptic loosening were revised. Surgery- and patient-related factors had no effect in results. Our results are encouraging, however, further study will be necessary to determine the incidence and fates of pseudotumors after MoM THA with a small head.

Isolated acetabular revision hip arthroplasty with the use of uncemented cup.

We evaluated the clinical and radiological results of isolated acetabular revision hip arthroplasty. Forty-three hips underwent isolated acetabular revision with uncemented cup and were followed up for an average of 76 months. The monoblock femoral stems were used in 20 hips and modular femoral stems in 23 hips. The average Harris Hip Score improved to 87 at last follow-up from 57 preoperatively. All femoral stems maintained stable fixation with bone ingrowth and no subsidence at last follow-up. Five hips with the monoblock stem underwent rerevision due to loosening of cup with osteolysis. The isolated acetabular revision is encouraging, but in reflection of the results of the monoblock head, the visual inspection of the femoral head is not enough for evaluation of its surface status.

Isolated Acetabular Revision With Ceramic-on-Ceramic Bearings Using a Ceramic Head With a Metal Sleeve

The purpose of this study is to evaluate results of isolated acetabular revision with ceramic-on-ceramic bearings using a ceramic head with a metal sleeve. A retrospective review of fifty-three hips was performed. The mean patient age was 49.9years and the mean follow-up period was 5.7years. The mean modified Harris hip score improved from 47.5, pre-operatively, to 84.7 at the time of last follow-up (P<0.001). Two patients reported squeaking of the hip. Three patients experienced loosening cup, necessitating re-revision surgery. There was a significant difference of acetabular bone defect between loose cup group and stable cup group (P=0.018). There were no ceramic fractures and no osteolysis. The survival rate of the acetabular cup at the mid-term follow-up was 94.3%. In conclusion, ceramic head with a metal sleeve can be a reliable option for isolated acetabular revision.

Cementless bipolar hemiarthroplasty for unstable intertrochanteric fractures in octogenarians

OBJECTIVE The aim of this study was to evaluate the clinical and radiographic outcomes of bipolar hemiarthroplasty with cementless stem for the unstable intertrochanteric fracture in octogenarians and to determine the influencing factors associated with subsidence of the stem. METHODS The study included the 143 hips of 139 patients (119 females, 20 males). Mean follow-up period was 3.8 (range: 2.2 to 9.0) years. The displaced lesser trochanteric fragment was reduced anatomically and fixed with 16-gauge stainless steel cerclage wire. Clinical outcomes included Harris Hip Score (HHS), thigh pain, groin pain and walking ability. Radiographic outcomes included stem fixation and stability, osteolysis, heterotopic ossification and subsidence. The stable reduction group was determined when anatomic reduction of posteromedial fragments was achieved with ≤1 mm gap of fragment. RESULTS Mean HHS was 82 (range: 78 to 99) at the final follow-up. Thirty-one hips (21.7%) experienced thigh pain and 19 (13.3%) groin pain. One hundred and twelve patients (80.6%) regained their pre-injury level of ambulation. All femoral stems showed osseointegration without aseptic loosening and osteolysis. The mean stem subsidence was 3.1±2.4 (range: 0 to 18) mm. The extent of subsidence was significantly higher in patients with unstable reduction. The survival rate was 94.2%. CONCLUSION Cementless bipolar hemiarthroplasty appears to be a suitable method for the treatment of intertrochanteric fracture in octogenarians. However, stable fixation of the posteromedial fragment is necessary to avoid stem subsidence.

Polyethylene Wear and Osteolysis in Uncemented Acetabular Component

Purpose: To investigate the influence of the linear wear rate of polyethylene, the osteolysis threshold of the linear wear rate, and the related factors on polyethylene wear in an uncemented metal-backed-cup of a primary total hip arthroplasty. Materials and Methods: This study examined 87 hips from 75 patients (57 men and 18 women) who had undergone a primary total hip arthroplasty with a minimum follow-up of five years. The mean age was 47.3 years (range, 25-68 years). The mean follow up period was 90 months (range, 60-148 months). The most frequent diagnosis was avascular necrosis of the femoral head. 18 Harris-Galante I and 69 Harris-Galante II cups, were used on the acetabular side, and 66 Anatomic and 21 Harris-Galantestems were used on the femoral side. Radiographic polyethylene wear was estimated using the method reported by Livermore, and the above mentioned factors that influence polyethylene wear were investigated and analyzed statistically. Results: The overall mean linear wear rate of polyethylene was 0.21 mm/year. The linear wear rate of 22 hips with osteolysis and 65 hips without osteolysis was 0.29 mm/year and 0.12 mm/year respectively, showing a significant difference (p=0.001). The patients with high activity had a significantly higher mean linear wear rate (0.28 mm/year) than that those patients with low activity (0.16 mm/year) (p=0.048). Patients younger than 40 year-old had a significantly higher mean linear wear rate (0.23 mm/year) than the patients older than 40 year-old (0.19 mm/year) (p=0.049). However, there were no correlations between the mean linear wear rate and gender, weight, diagnosis, the type of cup and the thickness of the polyethylene. Conclusion: The polyethylene wear rate in an uncemented metal-backed-cup was significantly affected by age and the activity of the patients, which strongly influenced the development of osteolysis. Therefore, in order to reduce the incidence of aseptic loosening due to osteolysis in young patients with high activity, a bearing surface with mean linear wear rate of 0.12 mm/year or less is recommended.