Staged Minimally Invasive Plate Osteosynthesis of Distal Tibial Fractures

PURPOSE: To assess the result of staged minimally invasive plate osteosynthesis (MIPO) for distal tibial fracture with an open wound or injured soft tissue. MATERIALS AND METHODS: In 20 patients (mean age, 47.8 year-old) with distal tibial fractures, there were 4 type A fractures and 16 type C fractures based on the AO classification system. Eight of the 20 patients had open fractures. MIPO was performed on average 23.9 days after bridging external fixation. At the final follow-up, we assessed the radiological results of bone union and alignment. Functional results were also evaluated by measuring the degrees of ankle motion and the American Orthopedic Foot & Ankle Society (AOFAS) scores. RESULTS: Seventeen of 20 cases (85%) achieved primary union at an average of 21.3 weeks. There were 3 cases of nonunion requiring a bone graft. The mean AOFAS score was 88.5 (range, 67~92) and the average range of ankle motion was 49.2degrees (plantarflexion: 37.4degrees, dorsiflexion: 11.8degrees). Complication included 2 cases of minor mal-alignment, 1 case of claw toe and 1 case of peroneal neuropathy. Patients over the age of 60 had lower functional results. Additional factors did not affect the final results. CONCLUSION: Staged MIPO may achieve satisfactory results in distal tibial fractures with soft tissue compromise, decreasing deep infections and soft tissue complications.

Anterior Plating and Ilio-sacral Screwing for Unstable Pelvic Injury / 대한정형외과학회잡지

PURPOSE: To evaluate the effectiveness of iliosacral screw fixation with anterior plating in the management of an unstable pelvic ring injury. MATERIALS AND METHODS: Nineteen patients with an unstable pelvic ring injury were enrolled in this retrospective study. All patients were followed up for at least 1 year. The mean age of the patients was 43 years. According to the AO-OTA classification, there were five B2 injuries, 11 C1 injuries, and 3 C2 injuries. After anterior fixation by plating, ilio-sacral screw fixation was performed percutaneously under the C-arm guide. RESULTS: All cases united except for 1 case of nonunion at the pubic ramus. The radiology results showed 9, 7, 2 and 1 case of anatomic, nearly anatomic, moderate and poor reduction, respectively. Sixteen out of 19 patients had a good or excellent functional result. Two moderate and one poor result were from an unsatisfactory reduction in a type C injury with the residual neurological signs. Screw misplacement with neurological compromise occurred in one patient but there were no adverse sequelae after its removal. Regarding the complications, there were two cases of screw loosening, two cases of anterior metal failures, and 1 case of a deep infection. CONCLUSION: Percutaneous ilio-sacral screwing with anterior plating may be a useful method for treating unstable pelvic ring injuries, and the reduction quality and neurological signs are important.

Comparison of Surgical Approach in Total Knee Arthroplasty: Midvastus and Medial Parapatellar Approaches

PURPOSE: In the incidence of lateral retinacular release, patellar tracking and clinical results were analyzed according to the surgical approach of total knee arthroplasty. MATERIALS AND METHODS: 286 osteoarthritic knees (228 patients) who had undergone patellar non-resurfaced total knee arthroplasty were analyzed and divided into two groups. Group I was 171 cases with midvastus approach, and group II was 115 cases with medial parapatellar approach. On the basis of patellar subluxation degree with no thumb test, we were deciding on whether the lateral retinacular release was needed or not. We radiologically evaluated patellar tracking, and clinically evaluated the range of knee motion, flexion contracture, and anterior knee pain. RESULTS: The lateral retinacular release was performed in 6 cases(3.5%) from group I, and 18 cases(15.7%) from group II (p=0.001). Patellar maltracking was observed in 26 cases, which were 14 cases(8.2%) from group I and 12 cases(10.4%) from group II (p=0.517). On the other hand, patellar maltracking was found in only 2 cases(8.3%) from retinaculum released group, and in 24 cases(9.2%) from retinaculum non-released group (p=0.623). Surgical approach and lateral retinacular release had no influence on clinical results. CONCLUSION: Midvastus approach could reduce the need for lateral retinacular release, but it had no influence on patellar maltracking and clinical results.

Accuracy of Limb Alignment in Total Knee Arthroplasty using Image-Free Navigation System: Comparison with Conventional Total Knee Arthroplasty

PURPOSE: We analyzed the comparative results of limb alignment after total knee arthroplasty using conventional method and image-free navigation system. MATERIALS AND METHODS: Total knee arthroplasties were performed in sixty-four patients(74 knees) with conventional method(37 cases)(Group A) and Orthopilot 4.0 image-free navigation system(37 cases)(Group B). We measured the femoro-tibial angle, femoral and tibial component angle in coronal and sagittal plane using the weight bearing whole leg radiograph taken 1-month postoperatively. RESULTS: Mechanical femoro-tibial angle was 1.4 degrees of varus in conventional group (Group A) and 0.8 degrees of varus in the navigation group (Group B) on average. Femoral and tibial component angle in the coronal plane was mean 1.8 degrees of varus and 0.7 degrees of varus in group A, 0.3 degrees of valgus and 0.5 degrees of varus in group B on average. Average femoral and tibial component angle in sagittal plane was 0.3 degrees of flexion and 0.8 degrees of anterior tilt in group A, 0.7 degrees of flexion and 1.7 degrees of anterior tilt in group B. There were no statistically significant differences between two groups in the femoro-tibial angle, femoral and tibial component angle in coronal and sagittal plane. But the ranges of deviation from desired angle were smaller in Group B than Group A. Statistically significant different results of the limb alignment (femoro-tibial angle and femoral component angle in coronal plane) were observed in 5 cases with severely bowed femoral shaft in group B (average femoro-tibial angle 0.9 degrees and femoral component angle in coronal plane 0.9 degrees varus) than group A (average femoro-tibial angle 3.5 degrees and femoral component angle in coronal plane 3.9 degrees varus). CONCLUSION: Accuracy of limb alignment in total knee arthroplasty using navigation system was not statistically significant difference than using the conventional method, but had better results in the deviation of mechanical femoro-tibial angle and femoral component angle in coronal plane than the conventional method, especially in severely bowed femoral shaft.

Osteoarthritis of the Elbow with Ulnar Neuropathy; Outerbridge-Kashiwagi Procedure through Posteromedial Approach / 대한정형외과학회잡지

PURPOSE: Elbow osteoarthritis with ulnar neuropathy was treated by a modified posteromedial approach, for decompression/transposition of the ulnar nerve and simultaneously with an Outerbridge-Kashiwagi procedure. The clinical result with these operative techniques is reported. MATERIALS AND METHODS: Average age of the patients was 51, which including 9 male and 2 female. There were 8 manual workers and one each of a clerk, a merchant and a house wife. The ulnar neuropathy was evaluated by the McGowan grading; one grade I, 4 grade II and 6 grade III. RESULTS: The ulnar nerve symptoms were relieved in all patients; 3 McGowan grade I, 5 grade II and 3 grade III, postoperatively. The pain subsided in all patients, with the exception of in one. The average range of motion was improved from 22.5-124degrees to 11.5-128.5degrees. CONCLUSION: A modified posteromedial approach is an effective method for both ulnar nerve decompression and the OK procedure, and provides an effective functional outcome.

Minimally Invasive Percutaneous Plate Stabilization of Proximal Tibial Fractures

PURPOSE: Despite of various treatment methods, proximal tibial fractures are common injuries that may be associated with poor outcomes and high rates of complications. To improve this, percutaneous plating technique was performed in the proximal tibial fractures. MATERIALS AND METHODS: Twenty-four proximal tibial fractures (AO 41A; 5, AO 41C; 12, AO 42; 7) were treated by percutaneous plating with either or both sides without bone graft. One was open fracture. RESULTS: All fractures were healed. The average time for fracture healing was 16.5 weeks (range, 8~24 weeks). Complications included a 1cm shortened case and two mal-alignments; a 6 degree valgus case and 5 degree varus case. There was one case of superficial infection, which healed after plate removal. But, there was no deep infection. Results were evaluated by modified Rasmussen score system, all patients had excellent or good result. CONCLUSION: Minimally invasive percutaneous plating technique can provide favorable results in the treatment of proximal tibial fractures.

Operative Treatment of Type III Coronoid Process Fractures

PURPOSE: To review the clinical results of eight cases of typeIII coronoid process fractures which were treated operatively. MATERIALS AND METHODS: Eight patients with coronoid type III fracture were reviewed retrospectively. All were men with an average age of 33. There were three isolated fractures, two elbow dislocations, two radial head and neck fractures, and one medial collateral ligament rupture. Open reduction and internal fixation through anterior approach with canulated screws was used. The patients were followed up for a mean of 31 months (24 to 60). RESULTS: Average active elbow joint motion at the most recent follow up was 105degrees. The average Mayo Elbow Performance Score was 76.9 (50 to 95). There was one excellent result, four good, two fair, and one poor. CONCLUSION: Early open reduction and stable internal fixation provided a reliable method for the treatment of type III coronoid process fractures. Any associated ligament injuries to the elbow and fracture comminution were considered as important prognostic factors.

Arthroscopic Analysis of Lateral Meniscal Variants

PURPOSE: We classified lateral meniscal variants according to types and tear pattern, and compared MR images with arthroscopic findings. MATERIALS AND METHODS: We reviewed 164 consecutive cases (158 patients) of arthroscopic examination for lateral meniscal variants during last ten years. We classified lateral meniscal variants into four types of arthroscopic appearance by modified Watanabe 's classification, and into six tear patterns by modifying O 'Connor 's classification. RESULTS: Regarding four types, 131 cases were complete; 25, incomplete; 4, Wrisberg, and 4, ringshaped. Six tear patterns were as follows: 33 simple horizontal, 21 complicated horizontal, 37 longitudinal, 27 central, 14 complex, and 12 radial. Among 31 cases with central tear or ring-shaped meniscus, we reviewed 25 MR images. Fifteen (60%) MRI 's were interpreted as displaced meniscal tear(bucket handle tear), 7 (28%) as discoid meniscal tear, and other 3 (12%) as simple tear: misinterpretation rate was 72%. Twelve patients (13 cases, 7.9%) had osteochondritis dissecans of lateral femoral condyle: nine patients (10 cases) of them had central tear, two patients (2 cases) had simple horizontal tear, and one patient (1 case) had ring-shaped meniscus. CONCLUSION: MR findings of ring-shaped meniscus or central tear should be differentiated from displaced meniscal tear(bucket-handle tear) considering history of trauma.

Femoral Lengthening with External Fixator over the Intramedullary Nail / 대한정형외과학회잡지

PURPOSE: The results and complications of femoral lengthening over an intramedullary nail with a external fixator in patients with limb length discrepancy were retrospectively reviewed. MATERIALS AND METHODS: After lengthening 22 femoral segments, all patients were followed-up for a mean of 3.2 years (range, 2 to 5.2 years). They ranged in age from 13 to 35 years (average age, 22.2 years) at the time of the index procedure. The mean lengthening was 5 cm (2.7 to 8.1 cm), and the external fixator was removed after a median 135.9 days (range, 59 to 210 days). The mean external fixation index was 23.8 days/cm of lengthening (range, 11.1 to 34.7 days/cm of lengthening). RESULTS: Nineteen patients achieved the length of their pre-operative goal. However, there were 3 failures with osteomyelitis and the removal of the nail, which had a past history of infection or open trauma. There were 4 knee joint complications when the lengthening was over 20%. These included three cases of a patella subluxation and one case of a posterior knee subluxation. In the other complications, there was one case of a collapse in the lengthened segment with a breakage of the locking screws. CONCLUSION: Although lengthening over a nail can reduce the duration of external fixation, caution is needed in order to prevent complications.

Ceramic-on-Ceramic Bearing Total Hip Arthroplasty in Young Patients with Osteonecrosis of Femoral Head / 대한정형외과학회잡지

PURPOSE: To evaluate the short-term clinical and radiographic results associated with use of the ceramicon-ceramic articulation uncemented total hip arthroplasty (THA) in patients less than fifty years old with osteonecrosis of femoral head. MATERIALS AND METHODS: Sixty-eight THAs with use of the ceramic-on-ceramic articulation were performed in fifty-nine patients who were younger than fifty years old with the implantation of an uncemented plasma coated Plasma cup and Bicontact stem. All patients were available for complete clinical and radiographic analysis after a mean duration of a follow-up of 31.6 months (range; 24-50 months). The average age of the patients at the index operation was 39.4 years (range; 16-49 years). Preoperative diagnosis was osteonecrosis of femoral head in all hips. The causative factors were idiopathic in twenty-one hips; alcohol abuse in twenty-eight hips, steroid in eleven hips, and posttraumatic in eight hips. Clinical evaluation was done by Harris Hip score (HHS). Radiographic evaluation was done in terms of stability of components and prevalence of osteolysis. RESULTS: The mean preoperative HHS of 61 points improved to 95 points at the time of the final follow-up. Excellent results were found in 57 hips (84%), good results were 11 hips (16%). No acetabular or femoral components were loosened radiographically. There was no evidence of osteolysis. There were two postoperative dislocation, one intraoperative femoral fissuring, and one transient sciatic nerve palsy. CONCLUSION: Short-term clinical and radiographic results associated with use of the ceramic-on-ceramic articulation uncemented THA in patients less than fifty years old with osteonecrosis of femoral head were excellent. However, longer-term follow up is needed.

Reconstruction of the Anterior Cruciate Ligament in over 40-year-old Patients / 대한정형외과학회잡지

PURPOSE: The purpose of the current study was to examine outcome after ACL reconstruction in patients over 40 years old, and to evaluate factors affecting outcome, such as, associated injuries and the preoperative period after injury. MATERIALS AND METHODS: Clinical results were obtained from 36 cases over 40 years old at the time of surgery. The average age was 45 years (40 to 67 years), and the average follow-up period was 27.6 months (12 to 85 months). Group 1 was composed of 13 cases with a less than 3 months preoperative period, and group 2 23 cases of more than 3 months. 31 cases had associated injuries and 5 cases did not. The parameters used were the Lachman test, KT-2000 arthrometry, Lysholm score, IKDC score, and return to sports activity before injury. RESULTS: The Lachman test was positive in 9 cases (25%) and mean side-to-side difference as determined by KT-2000 arthrometry was 3.9mm, however, there was no statistical difference between group 1 and group 2, regardless of associated injuries (p>.05). Lysholm score averaged 89.8 in total, and was 92.2 in group 1 and 88.5 in group 2, and 93.6 in those without associated injury and 89.2 in those with associated injury (p>.05). The IKDC score was normal (A) in 7 cases, nearly normal (B) in 25, abnormal (C) in 4. Twelve cases (92.3%) were graded A or B in group 1, and 20 cases (87%) were graded A or B in group 2 (p>.05). There were 5 cases (100%) of grade A or B in the group without associated injury and there were 27 cases (87.1%) of A or B in group with associated injury (p>.05). Return to sports activity before injury was possible in 19 cases (53%); 7 cases (53.8%) in group 1 and 12 cases (52.2%) in group 2 (p>.05), and 3 cases (60%) in the group without associated injury and 16 cases (51.6%) in the group with associated injury (p>.05). CONCLUSION: In patients over 40 years old with ACL injury, results can be successful after ACL reconstruction.

Treatment of Proximal Shaft Fracture of Tibia with Intramedullary Nail: Analysis According to AO Classification and the Poller Screw

PURPOSE: This was a retrospective study to evaluate the results of intramedullary nailing in proximal shaft fracture of tibia. We analyzed those results according to AO classification and Poller screw. MATERIALS AND METHODS: Thirty-three proximal tibial shaft fractures (32 patients) were followed for more than one year. In AO classification, there were 6 cases of type A, 14 cases of type B, and 13 cases of type C. We used Poller screws in 14 operations. We evaluated translation, angulation and nonunion after surgeries. RESULTS: Twenty-eight cases (85%) were united primarily, but nonunions occurred in 5 cases. Malalignment (angulation>5degree or translation>5 mm) was found in 14 cases (42%). In Poller screw used and non-used groups, the malalignment was respectively showed in 2 cases (14%) and 12 cases (63%). According to AO classification, nonunion was found in only type B with 5 cases (36%). CONCLUSION: Intramedullary nailing of proximal shaft fracture of tibia showed relatively lower rate of primary union. Especially, when initial fractures have a butterfly fragment, it showed the higher rate of nonunion. Moreover, the malalignment rate was relatively higher, yet it is possible to reduce the rate of malalignment by using Poller screw.

Grade III Tibia Open Fractures Treated with Unreamed Tibial Nailing

PURPOSE: This is a retrospective study to analyze the results of unreamed intramedullary nailing in grade III tibial open fracture. MATERIALS AND METHODS: Twenty-nine Gustilo-Anderson grade III tibial open fractures fixed with unreamed tibial nail were followed more than one year. Primary union rate, union time, infection, conversion to external fixation, ankle and knee function according to different grade of open, fracture level, AO classification, and muscle flap were evaluated. RESULTS: Primary union was achieved at sixteen fractures. There were three delayed union that achieved union twenty week after primary operation. And eight undergone secondary bone grafts which were done after inflammation sign subcided. Complications about infection were in five cases. Two cases were unable to maintain internal fixation due to deep infection, and three of superficial infection were treated with repeated debridement and antibiotics use. CONCLUSION: In grade III tibial open fracture, unreamed nailing with early soft tissue reconstruction and early prophylactic bone graft can be a good treatment.

Comparative Results of Arthroscopic Anterior Cruciate Ligament Reconstruction with Autologous Quadriceps Tendon-bone Versus Bone-patellar Tendon-bone

PURPOSES: We analyzed the comparative results of arthroscopic anterior cruciate ligament reconstruction using the autologous quadriceps tendon-bone versus the bone-patellar tendon-bone. MATERIALS AND METHODS: Thirty-three patients with ACL reconstruction using the autologous quadriceps tendon-patellar bone were evaluated (group 1). Control group were 33 patients underwent ACL reconstruction with autologous bone-patellar tendon-bone in similar period (group 2). The mean age was 29.7 years in group 1 and 23.5 years in group 2. The mean follow-up period was 20.8 months in group 1, and 21.8 months in group 2. We selected the patient with the similar age, conditions and operation methods. But group 1 with bone-to-tendon graft healing at one side was delayed rehabilitation program than group 2 (bone-to-bone healing). The final evaluation were range of motion, anterior knee pain, Lachman test, KT-2000 arthrometer, Lysholm score, IKDC evaluation, one-leg hop muscle function test. Student ttest was used for statistical analysis (p 0.05). According to the International Knee Documentation Committee (IKDC) rating system, normal were 30.3%, nearly normal 57.6%, abnormal 12.1% in group 1, and in group 2 normal was 24.3%, nearly normal was 63.6%, abnormal 12.1%. There were no statistical differences in normal and nearly normal rate between two groups (p> 0.05). Recovery of quadriceps strength by one-leg hop test was 78% of the normal knee in group 1, and 80% in group 2 (p> 0.05). CONCLUSION: There were no significant differences of clinical results in ACL reconstruction using between quadriceps tendon-bone and bone-patellar tendon-bone, but anterior knee pain. We consider that autologous quadriceps tendon-bone is a good alternative substitute in ACL reconstruction together with the bone-patellar tendon-bone.

Effect of Orthovanadate on Collagen and Fibronectin Synthesis, and Alkaline Phosphatase Activity in MC3E3-E1 Osteoblast cells / 대한정형외과학회잡지

PURPOSE: The purpose: of this study was to know the effect of inhibition of protein dephosphorylation on the synthesis of collagen and fibronectin (FN), alkaline phosphatase (ALP) activity, and the formation of bone nodule in MC3T3-E1 osteoblasts using orthovanadate (OVA) which is a potent protein tyrosine phosphatase (PTPases) inhibitor. MATERIALS AND METHODS: The synthesis of collagen, noncollagenous protein (NCP), and percent collagen in MC3T3-E1osteoblasts with or without OVA treatment according to concentration and time sequence was determined by incorporation of [3 H]-proline, synthesis of FN by [35 S] methionine incorproated immunoprecipitation after treatment with 100 M OVA for 24 hours, mRNA expression of collagen and FN by Northern blotting, activity of ALP by spectrophotometric method, and formation of bone nodule by staining method. RESULTS: OVA increased collagen and NCP synthesis concentration dependently, until 12 hours in short-time culture, and time dependently through the differentiation until 29 days, however, there was no significant effect on the percent collagen production. OVA increased percent collagen synthesis significantly at 6 hours, and decreased in a long time culture. Total FN synthesis and FN synthesis in cell layer were increased by OVA, however, FN synthesis in medium was not changed. OVA decreased collagen mRNA level dose-dependently and increased the steady-state level of FN mRNA. OVA inhibited activity of ALP in both short and long-time culture. OVA inhibited bone nodule formation in MC3T3-E1 osteoblasts. CONCLUSION: These results indicate that the inhibition of PTPase by OVA increased the synthesis of collagen, FN, and decreased ALP activity and it resulted in the inhibition of bone formation in MC3T3-E1 osteoblast cells.

Nonmodular One-Unit Cementless Acetabular Compoment in Primary Total Hip Arthroplasty: With Alumina to Polyethylene Articulation / 대한정형외과학회잡지

PURPOSE: Modular acetabular components have the potential of fretting and back side wear leading to osteolysis. The present study evaluated the outcomes of total hip arthroplasties (THAS) using a nonmodular cementless acetabular component with those of press-fit titanium mesh coatings fixed. MATERIALS AND METHODS: Eighty-two primary THAS in 75 patients were performed consecutively between April 1995 and August 1998. Sixty-two hips were eligible for follow up for an average 62 months. Mean patients age was 59 years. The clinical evaluation was performed using the modified Harris hip score (HHS), inguinal pain and limping. The radiologic evaluation included, component stability, polyethylene wear rate, pelvic osteolysis and the remodeling pattern around the acetabular component. RESULTS: Mean HHS improved from 50.2 points preoperatively to 90.5 points at the most recent follow up. All components were stable radiologically. The linear polyethylene wear rate was 0.07 mm/year. No pelvic osteolysis was found. Polar gaps found in 25 hips (40%) in postoperative radiographs and disappeared during follow up in 22 hips (88%). One hip was revised due to chronic unreduced dislocation. CONCLUSION: Total hip arthroplasty with a nonmodular cementless acetabular component seems to enhance satisfactory early midterm esults in terms of stability and acetabular remodeling with minimal wear and pelvic osteolysis.

Apoptosis of Cells of Interfacial Tissue of Aseptic Loosening and Osteolysis after Hip rthroplasty / 대한정형외과학회잡지

PURPOSE: To evaluate the relationships between the apoptosis induced by nitric oxide (NO), aseptic loosening and osteolysis, which are the most serious causes of failure after total hip arthroplasty. MATERIALS AND METHODS: Apoptosis of the inflammatory cells of interface tissues from 18 patients who underwent revision hip arthroplasty was identified by Terminal Deoxyribonucleotidyl Transferase-Mediated dUTP Nick End Labeling (TUNEL). The reaction to immunostaining of inducible nitric oxide synthase (iNOS), p53, Bax, Bcl2, and Ki-67 were evaluated. Six joint capsules obtained from six patients of femoral neck fracture were studied as controls. RESULTS: Sixteen (89%) of 18 interface tissues were positive for iNOS, p53, and Bax monoclonal antibody and twelve (67%) for Bcl2 and Ki-67 monoclonal antibody. All tissues were positive for TUNEL. In the control group of six joint capsules, only one (17%) was positive for iNOS and Bax, and three (50%) were positive for TUNEL. The incidences of apoptotic signals at the interfacial tissue of aseptic loosening and osteolysis were significantly greater than those of the control. CONCLUSION: The current study suggested that the apoptosis of inflammatory cells, due to oxidative stress by NO, might be involved in the development of implant loosening and osteolysis after total hip arthroplasty. This information might be crucial for the treatment and prevention of periprosthetic osteolysis and subsequent loosening.

Cementless Total Hip Arthroplasty using Metal on Metal Articulation / 대한정형외과학회잡지

PURPOSE: To evaluate the early midterm clinical and radiographic results of cementless total hip arthroplasty using Metasul metal-on-metal articulation. MATERIALS AND METHODS: Seventy-four (63 patients) of ninety three consecutive total hip arthroplasties (81 patients) using a metal on metal bearing surface and implanted from November, 1994 to April, 1998 with a minimum 3 year follow-up were analysed clinically and radiographically. The mean age at the time of index operation was 43.1 years (range; 17-65 years) and the mean follow up period was 61.2 months (range; 36-90 months). Clinical evaluation was performed by awarding Harris Hip scores (HHS). Radiographic evaluation was performed in terms of the stability of components, osteolysis, and wear rate. RESULTS: The average Harris hip score was 49.4 preoperatively and 91.4 at the most recent follow-up evaluation. Excellent or good results were found in 67 hips (90.5%). Two femoral components were loose radiographically, and one of the loose components was revised due to subsidence. Two acetabular components were revised (1 loosening and 1 continuous radiolucent line). One diffuse pelvic osteolysis was found around a stable component. Wear could not be measured radiographically. CONCLUSION: Compared to other bearing surface, total hip arthroplasty using a metal-on-metal bearing surface demonstrated very low wear rates and osteolysis at an average 5 year follow up results, however, a longer follow up is needed to evaluate wearinduced osteolysis.

Long-Term Results of Total Hip Arthroplasty using a Cemented Muller Prosthesis / 대한정형외과학회잡지

PURPOSE: The purpose of this study was to evaluate the long-term results of cemented Muller prostheses using a 32 mm metal femoralhead. MATERIALS AND METHODS: We reviewed 43 (31 patients) of 76 (55 patients) consecutive THAs, which were performed between April 1978and September 1985. The average duration of follow-up was 148 months (range, 65-279 months). The average age at the time of indexoperation was 44.4 years. Preoperative diagnosis was osteonecrosis in 31 hips, posttraumatic osteonecrosis in 8 hips, osteoarthritis in 2hips, and rheumatoid arthritis in 2 hips. We assessed cases clinically by Harris hip scores and radiographically by loosening and osteolysis, and measured polyethylene wear by the Livermore method. Kaplan-Meier analysis was used to evaluate survivability. We analyzedthe relationship and the statistical difference between wear and age, weight, height, body mass index, diagnosis, polyethylenethickness, and cup inclination (Pearson correlation's analysis, Student t-test, ANOVA test). The p-value was set p50 degrees) (p<0.05). CONCLUSION: Cemented Muller THAs using a 32 mm metal head showed poor survivability after an average follow-up of 12 years, due to the high incidence of loosening, the high rate of polyethylene wear and osteolysis. These results seem to be due to the relatively largenumber of operation for osteonecrosis of the femoral head in young patients and shortcomings of curved femoral stem design and the first generation cementing technique.

Experience of Revision Operation for Infected Total Knee Arthroplasty

PURPOSE: The purpose was to report the results of revision by two or more than three times operation using antibiotics impregnated cement block for the treatment of deep infection after total knee arthroplasty. MATERIALS AND METHODS: Between June 1999 and October 2001, 6 patients were reviewed retrospectively, who were treated for deep infection after total knee arthroplasty. At the time of reimplantation, the average age was 67 years. The average follow-up period was 26.7 months. Two coagulase-negative Staphylococcus aureus infections and one methicillin resistant Staphylococcus aureus infection were found on culture study. In three cases, group I, antibiotics impregnated cement block was inserted at the first operation. And then reimplantation was performed at 2nd operation as two-stage reimplantation. In another three cases, group II, debridement was done without removal of implant at the first operation. All three cases were failed to control infection. The infection was controlled and reimplantation was done at 4th time operation. The results were assessed according to the knee rating system of the Hospital for Special Surgery (HSS). Recurrence of infection or development of any other complication was evaluated. RESULTS: The average range of knee motion was 88 degrees at the time of diagnosis of deep infection, and it was 92 degrees at final follow-up. The average range of motion was 107 degrees in group I and 77 degrees in group II. Functional knee score of the HSS was improved from 69 points preoperatively to 88 points postoperatively. Each mean HSS score was 93 points in group I and 81 point in group II. There were no recurrence of infection during follow-up period after reimplantation. CONCLUSION: When the diagnosis of deep infection is confirmed in total knee arthroplasty, removal of the implants, thorough debridement and insertion of antibiotics impregnated bone cement blocks at the first operation is apparently better than only debridement without removal of implant. And two-stage reimplantation is better results in preserving knee joint function.