【Abstract】 Objective To disscuss the therapeutic method of the postoperative infection after hip arthroplasty andcompare the results of one-stage revision and two-stage revision. Methods From January 1999 to December 2005, 15 casesof infection after hip arthroplasty were treated, including 10 males and 5 females, with a mean age of 63 years (54-71 years).The locations were left hip in 8 cases and right hip in 7 cases. The first operation was hip prosthesis replacement in 6 cases andtatol hip arthroplasty in 9 cases. Infection occurred after 1 month in 6 cases and after 6 months in 9 cases. The preoperativetemperature and ruting blood test were normal, the mean erythrocyte sedimentation rate(ESR) was 61 mm/h (34-80 mm/h),mean C-reactive protein(CRP) was 11.7 mg/L(5.4-21.0 mg/L). The mean Harris score was 33 (25 - 40). The X-ray films showedthat periosteal reaction, osteolysis and loosening of prosthesis occurred. The time from the first operation to revision operationwas 1-41 months (mean 7.3 months). The results of bacterial culture were positive in 11 cases. One-stage revision wasperformed in 10 ases, two-stage revision was performed in 5 cases. Results Of 15 cases, 6 were classified as early postoperativeinfection, 9 cases as late chonic infection. The microorganism cultures results of joint aspiration or pus in sinus werepositive in 11 cases and negative in 4 cases before operation and during operation; 8 had staphylococcus epidermids infection,2 escherichia col i infection and 1 staphylococcus aureus infection. Incision of revision operation healed by first ention. Nore-infection, swell ing and tenderness occurred after 19 months (12-37 months) of follow-up. Pain of hip joint disappeared in14 cases, and only 1 case had mild pain when walking. ESR and CRP after operation decreased to normal range. The mean Harrisscore increased significantly to 84.2(79-92) after revision, showing significant difference when compared with that beforeoperation (P ＜ 0.05). Conclusion For postoperative infection after total hip arthroplasty, it is still possible to have satisfactorycl inical outcome by one-stage or two-stage revision as long as clear diaglosis and correct treatment can made.【Key words】 Hip arthroplasty Postoperative compl ications Infection Revision operation
Objective To analyze formation of the varus angle of the knee dueto osteoarthritis and to explore techniques of the soft tissue balance in the total knee arthroplasty(TKA). Methods One hundred patients with145 varus knees (18 males, 25 varus knees; 82 females, 120 varus knees) underwent TKA from January 1999 to December 2003. Their ages averaged 62.4 years (range, 45.80 years), and their HSS（hospital of special surgery）scores were 38.0±3.2 points. Before operation，all the patients were measured in the alignment of the lower extremity, accurate bonecutting was performed, and their static alignment was achieved. Then, the soft tissue release was made. The release performance consisted of 3 steps: release before the bone-cutting, release during the bone-cutting, and release after the bonecutting. Release of themedial ligament and capsule, elimination of the osteophytes, and release of thelateral patellar retinaculum were more important. Results The varus angles in these patients were 9.2±3.1° before operation. Among them,the varus angles caused by the soft tissue imbalance accounted for 53.2%，and caused by the bone structure accounted for 46.8%； and the latter caused by thetibia varus, 22.8%, and by the tibia plateau destruction, 24.0%. There was nosignificant difference between the varus angles caused by the soft tissue imbalance and the varus angles caused by the bone structure deformity (P＞0.05). According to the postoperative imaging studies, the correction degree for the varus angles by the bone-cutting was 4.3°, which represented 27.9% of the total corrected angles, and the correction degree for the varus angles corrected by the soft tissue balance was 10.7°, which represented 72.1% of the total corrected angles. The HSS scores were 87.0±4.5 points after operation, and the difference between preoperation and postoperation was significant. Conclusion The varus knee due to osteoarthritis results from the varus angle in the bone structure and the angles caused by the imbalance of the collateral ligaments and the soft tissues around the knee. The latter causative factor is more important in the formation of the varus knee and should only be corrected through the soft tissue release. The more important part to be released isthe attachments of the medial ligament and the posterior capsule. The release performance should be followed by the principles, i.e., step by step, tests at all the time, and avoidance of the excessive release.
【Abstract】 Objective To study the influence of close-box and open-box knee prosthesis on postoperative bloodloss in patients undergoing total knee replacement(TKR). Methods From June 2005 to December 2006, 108 atients with primaryknee osteoarthritis were treated with TKR. Closed-box knee prosthesis was used in 54 patients (Group A), including unilateral(Group A1, n =27)and bilateral (Group A2, n =27). There were 7 males and 47 females, aged 41-76 years; and the diseasecourse was 4-16 years. Open-box knee prosthesis was used in 54 patients(Group B), including unilateral (Group B1, n =27)andbilateral(Group B2, n =27). There were 8 males and 46 females, aged from 59-81 years; and the disease course was 8-26 years. Thepostoperative blood loss and perioperative blood loss were compared between groups. Results The postoperative blood losswas (890±352), (1 694±528), (1 068±386) and(2 065±622) mL in groups A1, A2, B1 and B2, respectively. There was no significantdifference between groups A1 and B1(P gt; 0.05). There was significant difference between groups A2 and B2(P lt; 0.05). The totalblood loss was (1 095±329), (2 082±594), (1 274±415) and (2 459±734) mL in groups A1, A2, B1 and B2, respectively. Therewas no significant difference between groups A1 and B1(P gt; 0.05). There was significant difference between groups A2 and B2(P lt; 0.05). Conclusion Closed-box knee prosthesis may play roles on reducing postoperative blood loss. The main influentialfactor for postoperative blood loss is operation techniques which includes reducing operation time and stanching thoroughlyduring operation.
Objective To investigate the rotational mismatch of total kneereplacement with medial 1/3 of tibial tuberosity as bony landmark in osteoarthritic patients with varus or valgus deformity. Methods Axial images on computed tomography of 62 knees (including 55 varus deformities and 7 valgus deformities) in 32 Chinese osteoarthritic patients who had total knee arthroplasty were analyzed, compared with that of 10 healthy knees. On images of the distal femur, the angle between the lines of surgical epicondylar axis(SEA) and posterior condylar axis was measured as posterior condylar angle (PCA), and on images of the proximal tibia, a baseline for the anteriorposterior axis of each component was drawn based on the SEA for the femur and the medial 1/3 of the tibial tuberosity for the tibia. The angle between these lines (Angle α) was defined as therotational mismatch between the components when they were aligned to the anatomic landmarks of each bone. Results The sulcus of medial epicondyle of femur could be identified on CT images of over 80% osteoarthritic knees; the median value of PCA was +2.36°, with an individual variation of 0° to +7.5°. Angle α was +6.45±3.68°(range, 0° to +11.8°) in 10 healthy knees, which increased significantly to +10.85±10.47°(range, 0° to +28.1°)in 55 varus knees (P＜0.05), which also increased significantly to +11.6±7.3°(range, -6.5° to +26.8°) in 7 valgus knees (P＜ 0.05). Conclusion With the medial 1/3 of the tibial tuberosity as the rotational landmark for the tibial component, there was a tendency to align the tibial component in external rotational position relative to the femoral component in knees with normal alignment, the rotational mismatch increased in Chinese osteoarthritic knees with varus and valgus deformity.
Objective To evaluate the clinical results of bioabsorbable interference screw in knee ligament reconstruction. Methods From April 2002 to August 2004, 39 patients with knee ligament injury were treated, including 33 males and6 females with a median age of 25 years (15 to 65 years). The involved ligament included 29 anterior cruciate ligament of knee(ACL), 6 posterior cruciate ligament of knee(PCL)，4 combined ACL and PCL, 3 medial collateral or lateral collateral ligaments of knee point and 1 posterolateral complex injury of knee. All of patients underwent anatomic ligament reconstructions under arthroscopy or open surgery by autografts and fixation with bioabsorbable interference screw. Results All 34 patients were followed up 6 to 28 months (mean 13.7months). The patients were evaluated by Lysholm knee functional scales, the knee scores were 43.6±13.4 before operation and 85.4±16.3 after operation, showing significant difference (Plt;0.05). There was no limitation of rangeof motion and loosening of the screw. However, one case suffered from infection, and 3 cases suffered from effusion and synovitis after surgery and recovered after management. Conclusion Bioabsorbable interference screw fixation is a reliable method in knee ligament reconstruction and is effective to restore knee joint stability.
Objective To explore the clinical application of the postanesthetic autologus donation and the post-operative transfusion during the knee and hipreplacement surgeries. Methods Thirty-three patients (17 males,16 females) admitted for the elective joint replacement surgeries from September 2004 to January 2005 were included in this study. Of the 33 patients, 5 were diagnosed with rheumatoid arthritis, 23 with femoral head necrosis, and 5 with knee osteoarthritis. Immediately after anesthesia, 400 ml of the blood was drawn and transfused after the surgery. The blood pressure was monitored during the blood drawing, postoperative blood parameters were recorded, surgical site drainage and signs of infections were observed, and the other clinical data were collected.Results Of the 33 patients, 27 only received autologoustransfusion, including 21 patients who underwent the unilateral hip replacement and 6 patients who underwent the unilateral knee replacement. All these 6 patients with the unilateral knee replacement received the blood drained from the surgical sites in addition to the blood obtained from the postanesthetic autologous donation. Another 6 cases with the bilateral hip and knee replacement received the blood drained from the surgical sites, the blood obtained from the post-anesthetic autologous donation and 400 ml of the allogeneic blood transfusion. The blood received postoperatively averaged 650 ml (range, 200-1 150 ml), haemoglobin(Hb) was averaged 88 g/L (68-102 g/L), and Hct was averaged 24.6% (20.5% 31.5%). Hb and Hct were lower after operation than before operation(Plt;0.01). Conclusion Postoperative blood transfusion following the postanesthetic and preoperative autologous donation can be successfully applied to most of the patients undergoing theknee or hip replacement so as to reduce complications of the allogeneic blood transfusion.
Objective To analyze the relationship between the collateral ligament attachment and the epicondylar axis with rotational alignment of the femoral component in the total knee arthroplasty(TKA).Methods Twenty normal cadaver knee joints were anatomized and 2 holes were drilled on the distal femur from the deep and superficial insertions of the medial collateral ligaments to the lateral condylar part, respectively. Then, all the knees were scanned by MRI on the sagittal plane, making the drilled hole located relatively to the posterior condylar joint surface on the axial plane, and the posterior condylar angle (PCA) and thecondylar twist angle (CTA) were measured.Results The colateral ligament had the deep and superficial parts, and the deep part was strained during the knee flexing. PCA and CTA were 4.50±1.26° and 7.10±0.30° respectively, and there was a significant difference between them(P＜0.05), which were significantly greater than those reported abroad. On the sagittal plane, there wasno significant difference between the radiuses of the posterior medial and lateral condylar circles (Pgt;0.05). The distance from the center of the posterior condylar circle to the deep insertion of the medial collateral ligament (MCL) (d1) was 4.22±0.20 mm, and the distance to the superficial insertionof MCL (d2) was 7.36±0.13 mm. The difference between d1 and d2 was significant(Plt;0.05). Conclusion The center of the posterior condylar circle passes from the deep insertion of the collateral ligament, which can be regarded as a fixed flexionextension axis of the knee. By releasing the different parts of the collateral ligaments, the balance of the flexion and extension gap canbe obtained, and then varus, valgus or flexed contracture deformity of the kneecan be realigned. Besides, the rotational orientation of the femoral prothesis can be made by a reference to the epicondylar insertion of the collateral ligament.