A Descriptive Analysis of the Hip and Knee Joint Replacement Procedures of the University of the Philippines - Philippine General Hospital (UP-PGH) from 2012 to 2018

@#OBJECTIVE: Hip and knee joint replacement procedures are an effective therapeutic intervention in treating severe joint disorders. Its use has been increasingly performed worldwide, including the Philippines, with its techniques constantly evolving and the science behind it improving. This study aims to describe the demographics, clinical profiles, and outcomes of arthroplasty patients by the Arthroplasty Service, Department of Orthopedics, University of the Philippines – Philippine General Hospital (UP-PGH). METHODS: The study is a descriptive and retrospective review of patients who underwent joint replacement procedures, both primary and revision arthroplasty, from January 2012 to December 2018. Patient demographics and clinical data of patients who underwent total joint arthroplasty at the UP-PGH were collected and evaluated. RESULTS: Data from 279 patients with 306 primary joint replacement procedures were analyzed. There were 195 total hip arthroplasty procedures (THAs) and 111 total knee arthroplasty procedures (TKAs) done. The mean age for THA patients was 55.6 years old, with more females (68.2%) with the left hip being more commonly affected (54.9%). The most common indication for THA was an untreated femoral neck fracture (23.1%) followed by avascular necrosis (20.5%). Cementless fixation was the most commonly used technique (61.5%). Meanwhile, the mean age for TKA was 64.5 years old, with the majority having degenerative osteoarthritis, and using cemented TKA fixation for all knees. A total of 37 revision arthroplasty cases were performed, with 34 in the hip and three in the knee, with infection being the most common overall indication (53%). CONCLUSION: The demographics, clinical profiles, and outcomes of the UP-PGH Arthroplasty Service are comparable to other centers internationally, and further emphasizes the satisfactory outcomes of these procedures. Meanwhile, suggested explanations for the subtle differences are discussed in this study.

Prosthetic joint infection: A major threat to successful total joint arthroplasty

Total joint arthroplasty (TJA) is one of the most common and reliable orthopaedic procedures that has significantly improved the quality of life of patients with degenerative joint diseases. Following the increase in the ageing population, availability of trained orthopaedic surgeons and advances in implantation procedures, demand for TJA both globally and in India is significantly increasing. Though TJA is one of the most cost-successful orthopaedic procedures, prosthetic joint infection (PJI) is one of the major complications of joint arthroplasty. Accurate diagnosis of PJI is challenging. Since total hip and knee arthroplasties comprises the majority of TJAs, this review focuses on the current understanding of incidence, risk factors, pathogenesis, causative microorganisms, diagnosis, treatment and prevention of PJI related to these two procedures.

Acetabulum Protrusion Following Ceramic Liner Fracture: A Case Report

@#Hip arthroplasty is an extremely satisfying treatment method for coxarthrosis which is in increasing use throughout the world. However, loosening of the prosthesis is a significant complication and to overcome this, ceramic liners are increasingly being selected. If the survival of ceramic surfaces is prolonged, there is a risk of fracture of the ceramic materials. New ceramic materials developed to overcome this problem are more resistant. The case presented here is of a patient in whom liner fracture developed following ceramic-ceramic hip arthroplasty. The ceramic femoral head was observed to have protruded into the defect created in the acetabular component. Acetabular revision was applied to the patient.

Radiological Stability after Revision of Infected Total Knee Arthroplasty Using Modular Metal Augments

PURPOSE: To evaluate the radiological stability according to the number of modular augments after revision of infected total knee arthroplasty (TKA). MATERIALS AND METHODS: Between February 2006 and September 2013, 37 patients (39 knees) followed > or =2 years after revision of infected TKA using modular metal augments for bone defects were reviewed retrospectively. We divided the patients into 3 groups according to the number of augments into group A ( or = augments, 7 knees) and evaluated the width of radiolucent zones around the implant at the last follow-up. RESULTS: There were 3 Anderson Orthopedic Research Institute type I, 33 type II, and 3 type III bone defects. The mean number of radiolucent zones of group A was 3 and the sum of width averaged 4.4 mm. In group B, the values were 4.8 and 6.2 mm, respectively. In group C, the values were 8.1 and 12.9 mm, respectively. The differences between the three groups were statistically significant. CONCLUSIONS: In revision TKA with modular metal augmentation caused by infected TKA, increased modularity can result in radiological instability.

Mid-term Results of Revision Total Hip Arthroplasty Using Modular Cementless Femoral Stems / 대한고관절학회지

PURPOSE: The purpose of this study was to evaluate the clinical and radiological results of revision total hip arthroplasty using modular distal fixation stems for proximal femoral deficiency. MATERIALS AND METHODS: Forty-five patients (47 hips) were analyzed more than 24 months after revision total hip arthroplasty that used modular distal fixation stems and was performed between 2006 and 2012. There were proximal femoral defects in all cases. Preoperative femoral defect classification revealed Paprosky type II in 31 cases, type IIIA in 7, and type IIIB in 9. The mean duration of follow-up was 53.4 (25-100) months. We evaluated the Harris hip score (HHS), walking ability according to Koval as clinical parameters, stem stability, and stem position change as radiographic parameters. Kaplan-Meier survival analysis was performed. RESULTS: The average HHS improved form 39.5 points to 91.3 points and walking ability also improved in most cases; all patients had stable fixation of the femoral stem. Postoperative complications included 5 cases of infection and 2 cases of dislocation. The survival rate with the end point of re-revision surgery due to infection or dislocation was 86% after 8-year follow-up. CONCLUSION: Cementless revision total hip arthroplasty using modular femoral stems is useful because the stems can be stably fixed on the diaphyseal portion of the femur, which has relatively good bone quality at mid-term follow-up.

Results of Revision Surgery and Causes of Unstable Total Knee Arthroplasty

BACKGROUND: The aim of this study was to evaluate causes of unstable total knee arthroplasty and results of revision surgery. METHODS: We retrospectively reviewed 24 knees that underwent a revision arthroplasty for unstable total knee arthroplasty. The average follow-up period was 33.8 months. We classified the instability and analyzed the treatment results according to its cause. Stress radiographs, postoperative component position, and joint level were measured. Clinical outcomes were assessed using the Hospital for Special Surgery (HSS) score and range of motion. RESULTS: Causes of instability included coronal instability with posteromedial polyethylene wear and lateral laxity in 13 knees, coronal instability with posteromedial polyethylene wear in 6 knees and coronal and sagittal instability in 3 knees including post breakage in 1 knee, global instability in 1 knee and flexion instability in 1 knee. Mean preoperative/postoperative varus and valgus angles were 5.8degrees/3.2degrees (p = 0.713) and 22.5degrees/5.6degrees (p = 0.032). Mean postoperative alpha, beta, gamma, delta angle were 5.34degrees, 89.65degrees, 2.74degrees, 6.77degrees. Mean changes of joint levels were from 14.1 mm to 13.6 mm from fibular head (p = 0.82). The mean HSS score improved from 53.4 to 89.2 (p = 0.04). The average range of motion was changed from 123degrees to 122degrees (p = 0.82). CONCLUSIONS: Revision total knee arthroplasty with or without a more constrained prosthesis will be a definite solution for an unstable total knee arthroplasty. The solution according to cause is very important and seems to be helpful to avoid unnecessary over-constrained implant selection in revision surgery for total knee instability.

Ceramic Head Fracture in Ceramic-on-Polyethylene Total Hip Arthroplasty

Revision rates of total hip arthroplasty have decreased after introducing total hip arthroplasty (THA) using ceramic component, since ceramic components could reduce components wear and osteolysis. The fracture of a ceramic component is a rare but potentially serious event. Thus, ceramic on polyethylene articulation is gradually spotlighted to reduce ceramic component fracture. There are a few recent reports of ceramic head fracture with polyethylene liner. Herein, we describe a case of a ceramic head component fracture with polyethylene liner. The fractured ceramic head was 28 mm short neck with conventional polyethylene liner. We treated the patient by total revision arthroplasty using 4th generation ceramic on ceramic components.

Total Knee Arthroplasty after Failed Unicompartmental Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: To identify the causes of failure after unicompartmental knee arthroplasty (UKA), and to evaluate considerations for surgical procedures and the results of revision total knee arthroplasty (TKA) performed after failure of UKA. MATERIALS AND METHODS: Eight hundreds and fifty-two cases of UKA were performed from January 2002 to June 2011. Forty-seven cases of failures after UKA were analyzed for the cause of the failures, and thirty-five cases of revision TKA after failure were analyzed for the operative findings and surgical technique. The clinical results were measured for thirty cases which were followed-up on at least two years after TKA. The mean duration of follow-up was four years and one month after revision TKA and the mean patient age at the time of surgery was sixty-five years. RESULTS: For the cause of failures after UKA, there were twenty-two cases of early loosening of prosthesis, seventeen cases of simple mobile bearing dislocation, five cases of infection, one case of fracture of medial tibial condyle and two cases of unknown origin pain. In operative findings of thirty-five cases of TKA after failed UKA, there were twenty-seven cases of bone defect requiring treatment and the mean thickness of the defect was 10.6 mm. For the treatment of bone defect, there were five cases of autogenous bone graft, twenty-one cases of metal blocks, and one case of autogenous bone graft with metal block. The stem was used in tibial implants for nineteen cases, and one case of use in tibial and femoral implants. For thirty cases where follow-ups were possible at least two years after operation, the mean knee score was improved from 68.2 to 85.2 and the mean knee function score was improved from 67.7 to 78.0 at the last follow-up, respectively. The mean range of knee motion was 107.2degrees pre-operatively, which was recovered to 120.7degrees after the operation. The mean tibiofemoral angle was changed from 1.7degrees of valgus to 5.2degrees of valgus. CONCLUSION: As shown in this study, the tibial bone defect was the most important problem in revision TKA after failure of UKA. Therefore, proper indication and accurate surgical technique using autogenous bone graft, metal block and stemmed implants would be able to achieve satisfactory results in revision TKA after failure of UKA.

Causes and Treatments of the Early Failure after Unicompartmental Knee Arthroplasty

PURPOSE: We wanted to evaluate the causes, treatments and preventive measures for early failure of unicompartmental knee arthroplasty (UKA) by performing an analysis of the cases. MATERIALS AND METHODS: We retrospectively analyzed 687 cases of UKA that had been performed from January 2002 to December 2006. There are 622 cases of the meniscal bearing type, 31 cases of the tracked bearing type and 34 cases of the fixed bearing type. All of the cases were performed by minimally invasive surgery. RESULTS: Early failures after UKA were seen in 36 cases, and these failures occurred from 4 months postoperatively to 5 years 7 months postoperatively. There were 20 mobile bearing dislocations, 18 femoral or tibial component loosenings, 4 infections, 1 medial tibial condylar fracture and 1 case of pain of unknown origin. The most common cause of the failed cases of the meniscal bearing type was bearing dislocation. All of the failed cases of the tracked and fixed types were from loosening of the component. Simple dislocations of bearing were treated by bearing change. All of the other cases were treated with revision TKA or UKA. CONCLUSION: Selection of an appropriate prosthesis and accurate surgical technique are needed to improve the clinical results and reduce failures. Open bearing change can be done for the cases of simple bearing dislocation, and revision TKA is needed if this is accompanied by other complications.

Acetabular Revision Using Uncemented Acetabular Cup

PURPOSE: The purpose of this study is to evaluate the clinical and radiological results of revision total hip arthroplasty with using impacted bone grafts and uncemented acetabular cups on the acetabulum with bone defects. MATERIALS AND METHODS: From June 1990 to March 2006, 131 revision total hip arthroplasties using an uncemented acetabular cup and impacted bone graft, were performed in 124 patients. The average follow-up period was 66 months. The clinical results were evaluated with the Harris hip score. The radiological results included the period of graft incorporation, the rate of resorption, the migration and the change of inclination of the cup. The failure rate and 13 year survival rate were analyzed. RESULTS: The Harris hip scores were 51.8 preoperatively and 82.5 postoperatively. The period of incorporation was a mean of 6.38 month. Most cases showed a resorption rate below 10%. The mean migrations of the acetabular cup were 1.37 mm superiorly and 1.20 mm medially. The mean change of inclination was 1.24 degrees. There were 5 re-revision surgeries. The failure rate was 3.8%. The survival rate of the revision that was done due to loosening was 94.9% at 13 years. CONCLUSION: Acetabular revision arthroplasty with bone grafts, and an uncemented cup is recommendable as it achieves favorable outcomes in terms of rapid incorporation of the grafted bone and stable fixation of the cup.

Management of Cyst on Anterior Tibia following Cementless Total Knee Arthroplasty: Case Report / 대한정형외과학회잡지

There are no reports of the occurrence of a cyst in the anteromedial side of the proximal tibia after cementless total knee arthroplasty in the Korean literature. The authors encountered 2 cases with a cyst, in whom the pain improved after cemented total knee revision arthroplasty. We report these cases with a review of the relevant literature.

Causes and Clinical Outcomes Associated with Re-revision Total Knee Arthroplasty

PURPOSE: To analyze the causes and clinical outcomes associated with re-revision total knee arthroplasty. MATERIALS AND METHODS: Eighteen cases of re-revision total knee arthroplasty (TKA) were performed between June 1996 and September 2006. The average patient age was 69.8 years, and the average follow-up period was 3.4 years. We evaluated the time interval between revision and re-revision arthroplasty and the causes of re-revision. Clinical outcomes were assessed using the Hospital for Special Surgery (HSS) knee rating score and determining the range of motion in the knee. RESULTS: The mean interval between revision and re-revision arthroplasty was 9 years 1 month. Causes of re-revision included 9 cases of polyethylene wear, 6 cases of aseptic loosening, 1 case of infection, and 2 cases of other causes. The average HSS score was 89.1, and the average range of motion was 111.1 degrees. For 5 cases of revision undertaken secondary to infected TKA, the interval between revision and re-revision arthroplasty was 9 years 3 months, and the cause of re-revision surgery was aseptic loosening in all cases. CONCLUSION: The main causes of re-revision surgery were polyethylene wear and aseptic loosening. Reasonable restoration of function was achieved in re-revision arthroplasty using appropriately selected implants, metal augmentation, structural allografts, and stems. When revising an infected TKA, it is important to achieve structural stability in the implant because of the possibility of late aseptic loosening.

Revision Total Knee Arthroplasty using NexGen(R) LCCK with Allograft / 대한정형외과학회잡지

PURPOSE: To analyze the clinical and radiographic results after revision total knee arthroplasty (TKA) using Nexgen(R) LCCK (Legacy(R) knee constrained condylar knee, Zimmer, Warsaw, IN) with allograft. MATERIALS AND METHODS: Twenty patients (21 knees) taken revision TKA were analyzed. The average age of the patients was 69.2 years old and the average of follow-up duration was for 2 year to 8 years 2 months (average 3 years 5 months). The clinical result and radiographic measurements were assessed using the Hospital for Special Surgery (HSS) knee rating score and the roentgenographic method of the American Knee Society. RESULTS: The mean interval from TKA to revision surgery was 6 years 4 months. In all cases, allograft was used. The average range of motion was increased from 93degrees to 107degrees, HSS score was increased from an average of 45 to 87 points. Postoperative femorotibial alignment was averaged 5.7degrees valgus. In all cases, radiolucency was below 4 scores and there was no loosening of implant. But, three radiopaque lines around a stem. There were wound dehiscence in 1 case and superficial infection in 2 cases. CONCLUSION: Satisfactory results were obtained in revision TKA using a NexGen(R) LCCK with allograft. But, this study is favorable for the long term follow-up.

The Causes of Revision Total Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: To assess the causes of revision total knee arthroplasty (TKA). MATERIALS AND METHODS: The causes of 90 revision total knee arthroplasties were analyzed in 84 patients between December 1996 and June 2006. The patients' history, medical records and radiographs were reviewed in order to detect the main cause of failure of the primary TKA. RESULTS: The causes of revision TKA are as follows: 34 infections (37.8%), 26 loosenings (28.9%), 17 polyethylene wears or breakages (18.9%), 5 stiffness (5.6%), 4 polyethylene dislocations (4.4%), 2 patellar dislocations (2.2%), 1 patellar component failure and 1 instability (1.1%). The mean interval from the index operation to the revision surgery was 59 months (1 month-20 years). CONCLUSION: Infection was the most common causes of revision TKA followed by loosening, wear or breakage of the polyethylene, stiff knee, and dislocation of the polyethylene.

The Methods and Results of Revision Total Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: To suggest operative methods for revision total knee arthroplasty (TKA) according to the causes of revision surgery. MATERIALS AND METHODS: The operative methods of 70 revision total knee arthroplasties in 64 patients between December 1996 and December 2004 were analyzed according to the causes. The mean follow-up period was 65 months (25-120 months). The range of motion and Hospital for Special Surgery (HSS) score were used for the clinical evaluation and the scoring system of American Knee Society was used for the radiographic evaluation. RESULTS: The mean periods of revision surgery from the initial operation was 59 months (1 month-20 years). Posterior cruciate retaining prosthesis was used in 8 cases, posterior cruciate substituting prosthesis in 14 cases, and constrained type prosthesis in 48 cases. The extension stem was required in 51 cases, metal augmentation in 34 cases, and structural allograft in 15 cases for bone defect treatment and firm fixation. The average range of motion improved from 88.8o preoperatively to 105.8o at the final follow-up. HSS score also improved from 60.5 to 87.6 points. The complications after revision TKA were 3 infections (4.3%), 1 patellar dislocation (1.4%), and 1 polyethylene dislocation (1.4%). CONCLUSION: Constrained type prostheses were needed in many cases of revision TKA. Satisfactory results were obtained using an additional structural allograft, metal augmentation, and extension stem for bone defect treatment and firm fixation.

Efficacy of Computer Assisted Surgery in Revision Total Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: The purpose of this study was to analyze the accuracy of the mechanical axis and implant positions postoperatively and to evaluate the radiology results of computer assisted navigation surgery for bone cutting and ligament balancing in revision TKA. MATERIALS AND METHODS: 13 consecutive revision TKAs were performed by a single surgeon with use of computer assisted surgery (CAS) from July 2004 to August 2005. At the revision, the mean age was 64.7 years. The mean interval from the index arthroplasty was 9.8 years. The cause of the revision included 11 cases of polyethylene wear and 2 cases of loosening. Two observers measured the mechanical axis, position of the implants, and level of joint lines. RESULTS: By observer I, the mechanical axis improved from varus 11.9degrees to valgus 1.5degrees, and the mean alpha, bets, gamma and delta angles were 95.3, 90.8, 3.9 and 87.6degrees respectively. From observer II, the mechanical axis improved from varus 11.6degrees to valgus 1.6degrees, and mean alpha, beta, gamma and delta angles were 95.5, 90.5, 4.1 and 87.9degrees respectively. The measured angles from observers I and II showed a good correlation. CONCLUSION: Accurate bone cutting and verification in each step are possible using real time information provided by the CAS. The mechanical axis, component positions, joint line could be checked and adjusted with feedback of navigation system. Information about flexion and extension gap and ligament balancing could be verified during revision surgery.

The Results of Revision Total Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: To analyze the clinical and radiographic results after revision total knee arthroplasty (TKA). MATERIALS AND METHODS: 122 revision total knee arthroplasties (mean follow up: 5 years 8 months) were performed. The causes of the revision TKA were; polyethylene wear in 77 knees, deep infection in 21, aseptic loosening in 17, and others in 7. Clinical findings & radiologic measurements were assessed using the Hospital for Special Surgery knee rating score (HSS score) & Bauer's methods, and by the roentgenographic method of the American Knee Society. RESULTS: After revision TKA, the average range of motion improved from 103degrees to 111degrees, and the average HSS knee score from 69 points to 90 points. A posterior stabilized prosthesis was used in 84cases (77%), medullary stem in 49cases (40%), femoral augmentation in 36 cases (29.5%) and structural allograft in 38 cases (31.1%). After revision TKA; the average femoro-tibial angle was corrected from 2.5degrees in valgus to 6.9degrees in valgus. Complications after revision TKA were; 1 dislocation of the patella, 1 wound disruption and 1 deep infection. CONCLUSION: The causes of revision TKA included polyethylene wear, deep infection and aseptic loosening. After revision TKA, satisfactory results were obtained using a posterior stabilized prosthesis, medullary stem and augmentation, and a structural allograft for large bone defect and soft tissue instability, respectively.

Acetabular Revision Total Hip Arthroplasty Using Uncemented Cup and Morselized Impacted Allograft / 대한정형외과학회잡지

PURPOSE: This study was undertaken to evaluate the clinical and radiographic results of acetabular revision arthroplasty using an uncemented big cup and a morselized impacted allograft. MATERIALS AND METHODS: This study involved 81 hips of 77 patients experienced over a 2 year period (2-8 years 10 months). The bone defects of the acetabulum were classified by AAOS classification and by the Paprosky classification. We inserted an uncemented hemispherical cup by press-fitting technique as large size as possible. Only morselized impacted allograft was used for the bone defect. RESULTS: The average Harris hip score was 95.9. One case (Paprosky type IIIB) received revision with only morselized allograft and failed to achieve initial stability. Therefore re-revision was performed with tricortical autograft and morselized allograft which has been well maintained until now for 3.5 years. Vertical migration and horizontal migration of more than 3 mm were noted in five cases and two cases, respectively. Rotational migration of more than 8 degree was not noted. A radiolucent line between bone and cup was seen in 9 cases, and a radiolucent line between host bone and grafted bone in 2 cases, this line was less than 2 mm large. CONCLUSION: We believe this method is a good option in revision acetabular total hip arthroplasty.

The Results of Revision Total Knee Arthroplasty / 대한정형외과학회잡지

PURPOSE: Results of revision total knee arthroplasties (TKAs) have provided relatively lower success rates than that of primary TKAs. We tried to evaluate the results and related problems of revision TKAs. MATERIALS AND METHODS: 27 revision total knee arthroplasties were evaluated clinically and roentgenographically with the American Knee Society Clinical Rating System. RESULTS: Pain score, range of motion, and knee score of aseptic and septic failures increased postoperatively after revision TKAs. Success rates of revision TKAs were 68.4% (13/19) for aseptic failure and 62.5% (5/8) for septic failure. We observed 9 complications including deep infections, wound dehiscence and superficial infections, fractures, and limitation of motion. CONCLUSION: Notable improvements were achieved in most of revision TKAs. However, relatively lower rate of success and higher rate of complications of revision TKAs emphasizes the importance of surgical technique handling significant bone loss, aggressive measure for complicated cases, and rehabilitation.

Revision Total Hip Arthroplasty Using Cementless Acetabular Cup / 대한정형외과학회잡지

PURPOSE: To evaluate the clinical and radiological results of revision total hip arthroplasty using cemetless acetabular cup and several kinds of morseled bone grafts. MATERIALS AND METHODS: We performed 20 cases of revision total hip arthroplasties between July 1993 and June 1996. Acetabular bone deficiency was classified as type I in 4 hips, type II in 13 hips, type III in 2 hips and type IV in one hip by AAOS classification. Autogenous bone graft was used in 10 cases, heterograft in 5 cases, allograft in 2 cases and a mixture with autografts and allografts in 2 cases. The average contact rate between cup and host bone was 33.5% in type I acetabular deficiency, 65.1% in type II, 50% in type III and 39% in type IV. RESULTS: The mean Harris hip score was 82.9 points at the last follow-up. Osseous union between host bone and graft bone occurred within 6 months in 14 cases. Radiological failure was noted in 8 cases at the last follow-up. Three cases were revised during the follow-up period. Five cases out of 7 cases in which the contact rate between acetabular cup and host bone was less than 50% were determined to be a radiologic failure. Only 2 cases of the 10 cases in which autogenous bone graft had failed grafts. The rate of complication was 7cases (35%). CONCLUSIONS: The usage of the hemispherical cementless acetabular cup with autogenous bone graft and increasing the contact rate between the acetabular cup and host bone could be a safe management method in revision total hip arthroplasty. We recomrnend avoiding the use of heterograft in cementless cup revision arthroplasty.