Clinical Result of a Staged Reimplantation of Fungus Related Periprosthetic Joint Infection after Total Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: Fungal periprosthetic joint infection (PJI) is a rare but devastating complication following total knee arthroplasty (TKA). On the other hand, a standardized procedure regarding an accurate treatment of this serious complication of knee arthroplasty is lacking. The clinical progress of staged reimplantation in patients who had fungus-related PJI after TKA was reviewed retrospectively. MATERIALS AND METHODS: Ten patients who had a fungal related PJI after TKA between 2006 and 2017 using staged reimplantation surgery were reviewed. These patients were compared with 119 patients who had a PJI in the same period. The failure rate of infection control, intravenous antimicrobial using the period, and the clinical results were evaluated by comparing the range of motion and Korean knee score (KKS) between pre-staged reimplantation and the last follow-up. RESULTS: In the fungal infection group, 7 out of 10 cases (70.0%) had failed in infection control using staged reimplantation and in the non-fungal group, 7 out of 119 cases (5.9%) had failed (p=0.04). In the non-fungal group, the mean duration of antibiotics was 6.2 weeks. In the fungus group, the mean duration of antibiotics was 15.3 weeks, which was 9.1 weeks longer (p < 0.001). The range of motion of the knee was increased in the two groups (p=0.265). At the last follow-up, the KKS was 71.01 points in the non-fungal group and 61.3 points in the fungal group (p=0.012). Erythrocyte sedimentation rate and C-reactive protein (CRP) decreased in the two groups, but the CRP was significantly different in the two groups (p=0.007). CONCLUSION: The treatment of fungus-related PJIs using staged reimplantation showed uneven clinical progress and unsatisfactory clinical improvements compared to non-fungal PJI. Therefore, it is necessary to consider the use of an antifungal mixed cement spacer at resection arthroplasty and oral antifungal agent after reimplantation.

Periprosthetic Fractures Following Total Knee Arthroplasty

Periprosthetic fractures after total knee arthroplasty may occur in any part of the femur, tibia and patella, and the most common pattern involves the supracondylar area of the distal femur. Supracondylar periprosthetic fractures frequently occur above a well-fixed prosthesis, and risk factors include anterior femoral cortical notching and use of the rotational constrained implant. Periprosthetic tibial fractures are frequently associated with loose components and malalignment or malposition of implants. Fractures of the patella are much less common and associated with rheumatoid arthritis, use of steroid, osteonecrosis and malalignment of implants. Most patients with periprosthetic fractures around the knee are the elderly with poor bone quality. There are many difficulties and increased risk of nonunion after treatment because reduction and internal fixation is interfered with by preexisting prosthesis and bone cement. Additionally, previous soft tissue injury is another disadvantageous condition for bone healing. Many authors reported good clinical outcomes after non-operative treatment of undisplaced or minimally displaced periprosthetic fractures; however, open reduction or revision arthroplasty was required in displaced fractures or fractures with unstable prosthesis. Periprosthetic fractures around the knee should be prevented by appropriate technique during total knee arthroplasty. Nevertheless, if a periprosthetic fracture occurs, an appropriate treatment method should be selected considering the stability of the prosthesis, displacement of fracture and bone quality.

Availability of Patella Resurfacing in Primary Total Knee Arthroplasty Through Evaluation and Analysis of the Patella in Revision Total Knee Arthroplasty / 대한정형외과연구학회지

PURPOSE: The aim of this study was to discuss about availability of patella resurfacing in primary total knee arthroplasty through evaluation and analysis of the patella in revision total knee arthroplasty. MATERIALS AND METHODS: The study was performed for 27 patients who could be followed up more than 12 months after having the revision TKA from March, 2004 to July 2008 among 105 patients (145 knees) who could be followed up more than 5 years after having primary TKA due to degenerative arthritis from 1989 to 1997. There were Group A (15 knees) which had patella resurfacing in revision TKA without patella resurfacing in primary TKA, Group B (12 knees) which had patella resurfacing in primary TKA, but didn't have patella resurfacing in revision TKA. There was difference of mean 11.2 years (6~15 years) between the time that the patients had primary TKA and the time that the patients had revision TKA. The patients consisted of 3 males and 24 females. The average age of the patients who had revision TKA was 76.2 years old (68~87). The Feller's patella score was used as clinical evaluation system after primary TKA, before and after revision TKA, and last follow-up. Ahlback's score was used by for the radiological evaluation of preoperative and postoperative outcome. And Outerbridge classification was used for the evaluation of group A which about wear of articular surface of patellofemoral joint in primary TKA and revision TKA, and positions of wear were classified. RESULTS: The Feller's patella score of group A, The outcome before revision TKA, 14.5 points, after 3 months TKA, 22.6 points, and 12 months follow-up, 24.2 points. The Feller's patella score of group B, The outcome before revision TKA, 24.2 points, after 3 months TKA, 24.3 points, and 12 months 24.8 points. The Ahlback score of group A decreased from 3.4 to 1.7 points, group B decreased from 1.6 to 1.5 points and group C decreased from 3.8 to 1.7 points. The Outerbridge classification of group A was mean 1.9 grade in primary TKA, and mean 3.6 grade in revision TKA. The wear of patella mainly occurred at medial facet. CONCLUSION: The patella resurfacing in primary TKA is considered as a useful treatment on the basis of these clinic and radiologic evaluation.

Two-Stage Revision Using a Modified Articulating Spacer in Infected Total Knee Arthroplasty

PURPOSE: To evaluate clinical results of two-stage revision using a modified articulating spacer for treatment of infected total knee arthroplasty (TKA). MATERIALS AND METHODS: We retrospectively reviewed 20 cases treated by two-stage revision arthroplasty using a modified articulating spacer under the diagnosis of infected TKA from January 2006 to December 2011. The mean follow-up period was 22.3 months. The first operation consisted of debridement after removal of the prosthesis, reinsertion of the femoral component after autoclaving, and implantation of antibiotic-loaded cement with a new polyethylene in the proximal tibia. RESULTS: The mean period between the primary TKA and the first stage operation was 39 months and between the first stage operation and the revision arthroplasty was 3.3 months. The average range of motion (ROM) increased from 69.8degrees preoperatively to 102.8degrees postoperatively (p<0.001). The mean Knee Society knee score increased from 33.8 points to 85.3 points (p<0.001). The mean Knee Society function score increased from 35 points to 87.5 points (p<0.001). The mean Hospital for Special Surgery score increased from 57.6 points preoperatively to 82.6 points postoperatively (p<0.001). Two cases (10%) were re-infected after the revision arthroplasty. CONCLUSIONS: Two-stage revision arthroplasty using an articulating cement spacer can be an effective therapy not only for the treatment of an infected TKA but also for recovery of knee ROM and function.

Augmentation with Transcortical Wiring of an Onlay-type Prosthesis for a Deficient Patella during Revision Total Knee Arthroplasty

The management of patellae with a severe bony deficiency during revision total knee arthroplasty is a challenging problem. However, using a technique of augmentation with transcortical wiring of an onlay-type prosthesis allowed the authors to revise a deficient patellae successfully. After making the decision to revise the existing patellar component, the procedure was found to be technically straightforward. Furthermore, the procedure does not require sophisticated instruments, only an onlay-type prosthesis, cement and wires. This technique entails fixing wires to the three pegs of the patellar component, passing the wires through drill holes in the anterior cortex and, after compression of a cemented prosthesis, augmenting the fixation by twisting the wires anteriorly. We believe that stable fixation and painless articulation will be obtained with the described technique for deficient patellae.

Minimum Two-year Results of Revision Total Knee Arthroplasty Following Infectious or Non-infectious Causes

PURPOSE: To compare clinical outcome of revision total knee arthroplasty (TKA) between the infected and non-infected groups. MATERIALS AND METHODS: This study compared the clinical and radiographic results of 21 infected and 15 non-infected revision TKAs at a minimum 2-years follow-up. Clinical evaluations were assessed using the range of motion (ROM), Hospital for Special Surgery (HSS) score, Knee Society Knee Score (KSKS), Knee Society Function Score (KSFS), and Western Ontario and McMaster Universities (WOMAC) score. Radiologic evaluations were assessed using the radiographic results of the American Knee Society and joint line change. RESULTS: Patients operated for non-infectious causes had significantly better postoperative ROM than the infected group (infected group, 101.7degrees; non-infected group, 117.8degrees). The infected group achieved significantly poor HSS (79.2 vs. 85.5), KSKS (75.5 vs. 86.6), KSFS (76.9 vs. 85.5), WOMAC (30.3 vs. 21.2) scores than the non-infected group. Postoperative joint line elevation was lower in the infected versus non-infected group (0.5 mm vs. 2.1 mm), but there was no significant difference. CONCLUSIONS: Revision TKA is an effective treatment that can provide successful results in the infected as well as non-infected patients. The overall results of non-infected revision were more satisfactory than infected revision.

Outcome of Isolated Tibial Polyethylene Insert Exchange after Total Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: We investigated the short term outcomes of isolated tibial polyethylene insert exchange after revision total knee arthroplasty. MATERIALS AND METHODS: We selected 18 cases from 17 patients among the 20 cases from 19 patients who took isolated tibial polyethylene insert exchange after mean 69 months-follow up of TKA, which was carried out from June 1991 to August 2003. Two cases were excluded on account of loss to follow-up. In all cases, isolated tibial polyethylene insert exchange was carried out from May 1998 to October 2008 in our institute and the mean follow-up period after operation was 48 (22-142) months. We evaluated the following clinical and radiologic aspects: range of motion, HSS score, average labor time, and BMI. Together, these factors were used in clinical evaluation while femorotibial angle and radiolucent line were used in radiologic evaluation. RESULTS: The average range of motion was 110.6 degrees and HSS score was 86.9 in follow up period. The average femorotibial angle was valgus 5.3degrees. The average labor time was 9.7 hours and BMI was 25.9. Although radiolucent line was found in 4 cases, there were all confirmed to be non progressive lesion less than 2 mm. Survival rate was 100% in Kaplan-Meier survival analysis. CONCLUSION: Selective isolated tibial polyethylene insert exchange can be the successful method for revision TKA in limited cases.

Results of Two Stage Revision of Infected Total Knee Arthroplasty (A Minimum 5-year Follow-up Analysis) / 대한정형외과학회잡지

PURPOSE: We report the results of 26 cases of revised total knee joint arthroplasty (TKA) that were followed up for more than 5 years. MATERIALS AND METHODS: On a retrospective basis, we reviewed 26 cases of infected TKA that underwent 2-stage revision between January 1993 and June 2005. All cases were followed up for more than 5 years. Clinical results were evaluated using Range Of Motion (ROM), Hospital for Special Surgery (HSS) score and radiographic results as part of the Knee Society Roentgenographic evaluation and Scoring system. The mean follow-up period was 70 months (ranging from 60 to 108 months). RESULTS: Infection recurred in 3 out of 26 cases. Patients without recurrence of infection showed improvement in ROM and HSS score, which had decreased with time (p<0.001) (ROM: pre-op. 47.1degrees, 1-year 89.5degrees, 2-year 87.1degrees, last follow-up 79.2degrees and HSS score: pre-op. 54.5, 1-year 85.7, 2-year 84.5, last follow-up 80.7). CONCLUSION: Infection recurred in 11.5% after revision arthroplasty. Outcomes of stage 2 revision arthroplasty were satisfactory at early follow-up, but worsened at the last follow-up.

Revision Total Knee Arthroplasty Using the PFC Sigma Knee System

PURPOSE: We wanted to analyze the causes of revision and the clinical and radiographic results after revision total knee arthroplasty. MATERIALS AND METHODS: Thirty-eight knees in 34 patients underwent revision total knee arthroplasty using the PFC(R) Sigma revision system between March 1999 and May 2005. The average patient age was 71.2 years, and the average follow-up period was 6 years 7 months (range: 4 years~10 years 2 months). We evaluated the time interval between the primary and revision arthroplasty and the causes of revision. The clinical outcomes were assessed using the knee score and the functional score of the Knee Society Scoring system (KSS system), and the radiographic measurements were assessed using the roentgenographic method of the American Knee Society. RESULTS: The mean interval between primary and revision arthroplasty was 6 years 3 months. The causes of revision included 25 cases of aseptic loosening and osteolysis, 7 cases of infection, 3 cases of joint stiffness and 3 cases of polyethylene problems. At the follow up, the mean preoperative knee and functional scores improved from 45.1 points to 84.5 and 37.2 to 78.2, respectively. Radiographycally, the average femorotibial angle was corrected from 2.2degrees in valgus to 6.5degrees. The radiolucency score was below 4 in all the cases. The complications after revision arthroplasty were 2 cases of superficial infection and 1 case of wound dehiscence with a skin defect. CONCLUSION: The main causes of revision arthroplasty were aseptic loosening and osteolysis. Satisfactory results were obtained using the posterior cruciate ligament and substituting the PFC(R) Sigma knee system with appropriately selected metal augmentation and an allograft. This study showed favorable results on long term follow-up.

Factors Affecting the Range of Motion after Revision Total Knee Arthroplasty

PURPOSE: We aimed to analyze the clinical results and investigate the factors that affect the range of motion (ROM) after revision total knee arthroplasty. MATERIALS AND METHODS: We measured the range of motion from 61 knees of 55 patients who underwent revision total knee arthroplasty using the Nexgen(R) LCCK and we investigated the factors affecting the postoperative ROM, including age, the body mass index (BMI), the preoperative ROM, deformity, causes of revision (septic vs. aseptic) and the type of polyethylene inserts (constrained vs. posterior-stabilized). The clinical results and radiographic findings were assessed using the American Knee Society Score and the roentgenographic method of the American Knee Society. RESULTS: The mean range of motion was improved from 113.7degrees to 127.2degrees. The preoperative ROM (p=0.000) and diagnosis (p=0.006) significantly influenced the postoperative ROM, yet age (p=0.386), BMI (p=0.054), deformity (p=0.218) and the type of polyethylene insert (p=0.195) were not related to the postoperative knee ROM. The American Knee Society Knee Score and Function Score on average was improved from 31.7 and 27.9 points to 86.7 and 64.7 points, respectively. CONCLUSION: The range of motion and clinical results were satisfactory after revision total knee arthroplasty using the Nexgen(R) LCCK, and the important factors affecting the range of motion after operation were the preoperative ROM and the causes of revision. The range of motion after arthroplasty using the constrained type polyethylene insert was not inferior to that using the posterior-stabilized insert.

Delayed Repair with Augmentation using Achilles Allograft of Old Ruptured Patellar Tendon after Revison Total Knee Arthroplasty: A Case Report / 대한정형외과학회잡지

The rupture of the patellar tendon after total knee arthroplasty (TKA) is rare but serious complication resulting in a severe dysfunction in the extension mechanism. There are a few reports on the treatment of this condition. However, there is still some controversy regarding the choice of proper management. There is no report of the patellar tendon augmentation or reconstruction in this condition in the Korean literature. We report a case of an old patellar tendon rupture in 70-year old patient that occurred at 5 months after a two stage revision for an infected TKA and was treated satisfactorily by delayed repair with augmentation using an Achilles allograft.

The Biomechanical Effect of Stem Design and Methods of Fixation in Revision Total Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: This study examined the effect of the stem design and method of fixation on biomechanical features around a stem tip in revision total knee arthroplasty using finite analysis. MATERIALS AND METHODS: A 3D Finite element model was reconstructed for a CT scan of the normal tibia from a 26 year old male and the CAD model of total knee arthroplasty revision was developed. The design change in the stem such as the length, diameter, slot, press fit and coefficient of friction was performed. The contact pressure, von-Meises stress around the stem and the micromotion were evaluated. RESULTS: A longer length and larger diameter press fit stem significantly increased the contact pressure and stress at the end of stem. The distal slot reduces the contact pressure and stress at the end of stem. Less displacement between the tibial component and bone was noted in the increased coefficient of friction. CONCLUSION: A stem with shorter length sufficient to engage proximal diaphysis, a closer diameter of the proximal canal and a minimal press fit can be used to reduce the contact pressure and stress if the patient's surgical anatomy such as bone loss and quality is tolerable in revision total knee arthroplasty.

Structural Allograft for Management of Severe Bone Defectin Revision Total Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: To analyze the clinical and radiographic results after revision total knee arthroplasty using a structural allograft for large bone defects. MATERIALS AND METHODS: 184 cases of revision total knee arthroplasty were performed from January 1992 to February 2003. Among them, 52 knees in 48 patients with the use of structural allograft for the management of large bone defects were retrospectively reviewed. Those 52 knees have been followed until recently. The average follow-up period was 5 years and 6 months. Fresh-frozen femoral head was used as the structural allograft in all knees. The clinical rating system of the American Knee Society was used for the clinical assessment. Union at the allograft-host bone junction, femoro-tibial angle and periprosthetic radiolucent lines using a radiographic evaluation of American Knee Society were analyzed radiographically. RESULTS: At the final follow-up, the mean preoperative knee and function score improved from 38.6 points to 82.6 and 30.3 to 76.4, respectively. Radiographically, union of the allograft to the host bone was observed in all knees. The average femoro-tibial angle was corrected from 1.8 degrees in valgus to 6.2 degrees. The radiographic evaluation revealed no evidence of loosening. CONCLUSION: Revision total knee arthroplasty using a femoral head allograft is an appropriate surgical method for treating large bone defects.

Clinical Outcomes of Infective and Non-infective groups in Revision Total Knee Arthroplasty

PURPOSE: To compare clinical outcomes of infective and non-infective groups in revision total knee arthroplasty. MATERIAL AND METHODS: From December 1993 to December 2001, 29 cases of revision total knee arthroplasty were performed in 27 patients. The mean age at the time of surgery was 64.2 years (48~74). The average follow-up was 45.4 months (24~90). All cases were divided into two groups (fourteen noninfective and fifteen infective groups). The clinical results were evaluated according to range of motion, Hospital of Special Surgery score, Knee Society score and tibiofemoral angle. The causes of revision in noninfective group were aseptic loosening in eleven, instability in two, and femoral periprosthetic fracture in one. RESULTS: There was a significant improvement of range of motion, Hospital for Special Surgery Knee score and Knee Society score at the final follow-up compared with the pre-operative status. The above three evaluation criteria showed no significant difference between the two groups except higher further flexion in non-infective than infective group. Preoperative average tibiofemoral angle was varus 1.4degrees in non-infective group and valgus 2.6degrees in infective group (P0.05). There were three complications in infective group, which were two reinfections, and one avulsion of osteotomized tibial tubercle. CONCLUSION: Preoperative planning, choice of proper implants, meticulous management of bony defect and soft tissue enabled successful results in infective group as well as non-infective group except less further flexion in infective group.

Two Stage Revision using Custom Articulating Spacer in an infected TKA: A Novel Method for an Intraoperative Construction of an Articulating Spacer / 대한정형외과학회잡지

PURPOSE: This paper reports a novel technique to create an antibiotic spacer for the treatment of infected total knee replacements (TKA) with surface contours similar to that of the original TKA. MATERIALS AND METHODS: This new technique involved the intra-operative construction of a custom mold made from bone cement along with the removed implant. Twelve consecutive patients treated with this technique were reviewed in the aspect of the degree of flexion, difficulty in exposure at the 2nd stage reimplantation, and complications related to the technique. The functional status was evaluated using the Knee Society score. RESULTS: The degree of flexion was 85 (40-130) preoperatively and 100 (70-110) prior to reimplantation. The postoperative flexion was 112 (90-140) at 6 weeks, 108 (70-140) at 3 months, and 110 (75-140) at 1 year postoperatively. A rectus snip was required in 8 out of 12 cases. Other extensile approaches were not needed. The knee society score was significantly improved from 30/24 to 87/80. No specific complications were noted at the final follow-up. CONCLUSION: This technique allows the immediate stability and mobility after the first stage of reimplantation. This technique offers ease and convenience of surgical technique without considerable increase in surgical cost or time. In addition, it eliminates the requirement for costly commercial mold or special pre-manufactured implants.

The Management of Bone Defects in Revision Total Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: Bone defects in revision TKA were classified according to AORI (Anderson Orthopedic Research Institute) system and results of the treatment are reported according to this classification. MATERIALS AND METHODS: The results of 24 revision TKAs operated from Mar. 1991 to Apr. 1999 were analysed. Fourteen knees had type 1 tibial defects, four knees had type 2 and six knees had type 3. On the femoral side, twelve knees had type 1, four knees had type 2 and seven knees had type 3 defects. Cement and chip bone grafts were mainly used to fill bone defects in type 1, wedges or blocks in type 2 and structural allograft combined with the other methods in type 3. Results were evaluated using the knee and functional scores of the American knee society. RESULTS: The analysis of the results according to the method of treatment- cement filling, chip bone graft, structural bone graft, wedge or blocks and custom made prosthesis- revealed improvements of knee scores in all groups except for custom made prosthesis. CONCLUSION: Satisfactory clinical results were obtained for the management of bone defects according to the AORI classification system in revision total knee arthroplasty.