Scott Sporer - Profile on Academia.edu (original) (raw)
Papers by Scott Sporer
(iii) Cementless femoral revision: The role of monoblock versus modular stems
Current Orthopaedics, Jun 1, 2006
ABSTRACT
Journal of Arthroplasty, Jun 1, 2010
Vascular injury is a rare but devastating complication of total hip arthroplasty. We present 2 ca... more Vascular injury is a rare but devastating complication of total hip arthroplasty. We present 2 cases of external iliac artery injury that complicated the removal of a chronically infected total hip arthroplasty where the acetabular component had migrated medial to Kohler's line. In both cases, hemostasis and reperfusion were achieved with the assistance of a vascular surgeon. This report describes the diagnosis, treatment, and associated risk factors for this rare complication. The combination of deep infection and medial migration of the acetabular component represents a high-risk situation for vascular injury. We advocate preoperative consultation with a vascular surgeon in this setting.
Journal of Bone and Joint Surgery, American Volume, Apr 1, 2005
The bone & joint journal, Jul 1, 2018
The aim of this study was to examine the results of the acetabular distraction technique in achie... more The aim of this study was to examine the results of the acetabular distraction technique in achieving implantation of a stable construct, obtaining biological fixation, and producing healing of chronic pelvic discontinuity at revision total hip arthroplasty. We identified 32 patients treated between 2006 and 2013 who underwent acetabular revision for a chronic pelvic discontinuity using acetabular distraction, and who were radiographically evaluated at a mean of 62 months (25 to 160). Of these patients, 28 (87.5%) were female. The mean age at the time of revision was 67 years (44 to 86). The patients represented a continuous series drawn from two institutions that adhered to an identical operative technique. Of the 32 patients, one patient required a revision for aseptic loosening, two patients had evidence of radiographic loosening but were not revised, and three patients had migration of the acetabular component into a more stable configuration. Radiographically, 22 (69%) of the cohort demonstrated healing of the discontinuity. The Kaplan-Meier construct survivorship was 83.3% when using revision for aseptic acetabular loosening as an endpoint. At the time when one patient failed due to aseptic loosening (at 7.4 years), there were a total of seven patients with a follow-up of seven years or longer who were at risk of failure. The acetabular distraction technique demonstrates encouraging radiographic outcomes, with healing of the discontinuity in over two-thirds of our series. This surgical technique permits biological fixation and intraoperative customization of the construct to be implanted based on the pattern of the bone loss identified following component removal.
Nephrotoxicity After the Treatment of Periprosthetic Joint Infection With Antibiotic-Loaded Cement Spacers
Journal of Arthroplasty, Jul 1, 2018
Treatment of periprosthetic joint infections commonly involves insertion of an antibiotic-loaded ... more Treatment of periprosthetic joint infections commonly involves insertion of an antibiotic-loaded cement spacer (ACS). The risk for acute kidney injury (AKI) related to use of antibiotic spacers has not been well defined. We aimed to identify the incidence of and risk factors for AKI after placement of an ACS. We performed a prospective cohort study of patients with an infected primary total hip or knee arthroplasty treated with ACSs with vancomycin, gentamicin, and tobramycin. Serum creatinine and glomerular filtration rate data were collected at baseline and weekly intervals for 8 weeks. Patients were classified into Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease (RIFLE) stages to determine incidence of AKI. Risk factors for kidney injury were identified via regression analysis. A total of 37 patients (20 total knee arthroplasty and 17 total hip arthroplasty) were included. During the 8 weeks after ACS placement, 10 patients (27%) fit RIFLE criteria for kidney injury and 2 patients (5%) fit RIFLE criteria for kidney failure. No baseline patient characteristics were associated with development of AKI. Patients should be monitored closely for development of AKI after placement of ACSs for the treatment of periprosthetic joint infection. Further research into minimizing risk for AKI is warranted.
Postoperative Pain Management After Primary Total Knee Arthroplasty: The Value of Liposomal Bupivacaine
Journal of Arthroplasty, Nov 1, 2016
Multimodal pain protocols have been proposed to achieve improved long-acting postoperative analge... more Multimodal pain protocols have been proposed to achieve improved long-acting postoperative analgesia. Controlling postoperative pain after joint arthroplasty is especially important as it relates to patient satisfaction and outcomes. The purpose of this study was to compare the postoperative pain, time to ambulation, and overall narcotic usage between patients who received either a femoral nerve block with a periarticular bupivacaine injection or a periarticular bupivacaine and extended-release liposomal bupivacaine injection after primary total knee arthroplasty. A total of 597 consecutive primary total knee arthroplasties performed between September 1, 2012 and August 31, 2014 received preoperative celecoxib, oxycodone, and transdermal scopolamine. Intraoperatively, patients either received a single-dose bupivacaine femoral nerve block along with 30-mL 0.25% bupivacaine periarticular injection (group A) or a 60-mL periarticular injection alone (20-mL liposomal bupivacaine, 30-mL 0.25% bupivacaine, and 10-mL saline; group B). The postoperative pain scores, narcotic usage, and time to ambulation were retrospectively collected from the electronic medical record. These outcomes were compared between treatment groups. There were 325 patients in group A compared with 272 in group B during the time frame. There was no difference among age, gender, race, and body mass index between the groups. Group B demonstrated a decreased need for breakthrough pain medication (16.9% vs 36.3% P < .001), decreased pain 12 hours postoperatively (3.2 vs 3.6 P < .003), and an earlier time to ambulation (29.5 hours vs 32.2 hours, P < .017). There was no difference in hospital length of stay (2.8 vs 2.6 days, P = .123). On controlling for demographic factors, patients in group B were able to ambulate 2.3 hours earlier than those in group A (coefficient = -2.3, P = .049). Liposomal bupivacaine resulted in a decrease need for breakthrough pain medication, improved pain scores at 12 hours, and an earlier time to ambulation compared to a combined femoral nerve block and periarticular bupivacaine injection.
The bone & joint journal, Nov 1, 2014
A pelvic discontinuity occurs when the superior and inferior parts of the hemi-pelvis are no long... more A pelvic discontinuity occurs when the superior and inferior parts of the hemi-pelvis are no longer connected, which is difficult to manage when associated with a failed total hip replacement. Chronic pelvic discontinuity is found in 0.9% to 2.1% of hip revision cases with risk factors including severe pelvic bone loss, female gender, prior pelvic radiation and rheumatoid arthritis. Common treatment options include: pelvic plating with allograft, cage reconstruction, custom triflange implants, and porous tantalum implants with modular augments. The optimal technique is dependent upon the degree of the discontinuity, the amount of available bone stock and the likelihood of achieving stable healing between the two segments. A method of treating pelvic discontinuity using porous tantalum components with a distraction technique that achieves both initial stability and subsequent long-term biological fixation is described.
Revision Total Hip Arthroplasty
Clinical Orthopaedics and Related Research, Dec 1, 2003
Femoral revision with a 7-inch or 8-inch fully porous-coated stem may not provide reliable long-t... more Femoral revision with a 7-inch or 8-inch fully porous-coated stem may not provide reliable long-term results in patients with moderate bone loss. The purpose of this study was to evaluate the limits of fully porous-coated stems and to create a treatment algorithm for femoral deficiencies. Fifty-one patients with either a 10-inch or 9-inch calcar fully porous-coated stem, 10 patients with impaction bone grafting, and 10 patients with a modular tapered stem were evaluated at an average 4.2 years postoperatively. The mechanical failure rate among the 9-inch and 10-inch fully porous-coated stems was 0% in Type III B defects with femoral canals less than 19 mm (15 patients), 18% in Type IIIB defects with femoral canals greater than 19 mm (2 of 11 patients) and 37.5% in Type IV defects (three of eight patients). There were no mechanical failures observed among the bone packing or modular tapered stems. Patients with Type IIIB defects and a femoral canal less than 19 mm can be treated successfully with either a 10-inch or 9-inch calcar fully porous-coated stem. However, patients with Type IIIB defect and an endosteal canal greater than 19 mm or a Type IV defect require alternative methods of reconstruction such as a modular tapered stem or a bone packing procedure.
Clinical Orthopaedics and Related Research, Dec 1, 2004
Methods.-A case-control study was performed to identify risk factors for prosthetic joint infecti... more Methods.-A case-control study was performed to identify risk factors for prosthetic joint infections (PJI). Antibiograms of isolates associated with PJI were reviewed. Molecular typing of available MRSA isolates was done using pulsed field gel electrophoresis (PFGE). Nares cultures of health care workers who provided care to those orthopedic patients were obtained. Results.-Over a 13-month period (January 2003-January 2004), 9.5% of patients with prosthetic hip (THA) or knee (TKA) joint surgery developed PJI (7 TKA and 2 THA). The mean time to development of PJI was 20 days. Five infections were caused by CA-MRSA and 3 by methicillin-susceptible S aureus; one was culture negative. All CA-MRSA isolates had identical antibiograms (resistant to -lactams and erythromycin; susceptible to clindamycin, trimethoprim-sulfamethoxazole, rifampin, gentamicin, levofloxacin, and vancomycin). Molecular typing of 2 available CA-MRSA isolates revealed that these were the USA300 clone; these isolates were PVL+ and carried SCCmec IV. CA-MRSA was not recovered from nares cultures from 31 health care workers. In multivariate analysis, TKA (OR, 8.1; 95% CI: 1.3-48.1) and surgery time >180 minutes (OR, 7.4; 95% CI: 1.4-39.6) were associated with PJI. Conclusion.-We have demonstrated that the CA-MRSA USA300 clone is no longer just a cause of community-acquired infections but has also emerged as a cause of health care-associated infections, causing PJI at our institution.
Perioperative Testing for Joint Infection in Patients Undergoing Revision Total Hip Arthroplasty
Journal of Bone and Joint Surgery, American Volume, Sep 1, 2008
While multiple tests are used to determine the presence of infection at the site of a total hip a... more While multiple tests are used to determine the presence of infection at the site of a total hip arthroplasty, few studies have applied a consistent algorithm to determine the utility of the various tests that are available. The purpose of the present study was to evaluate the utility of commonly available tests for determining the presence of periprosthetic infection in patients undergoing revision total hip arthroplasty. Two hundred and thirty-five consecutive total hip arthroplasties in 220 patients were evaluated by one of two surgeons using a consistent algorithm to identify infection and were treated with reoperation. Receiver-operating-characteristic curve analysis was used to determine the optimal cut-point values for the white blood-cell count and the percentage of polymorphonuclear cells of intraoperatively aspirated hip synovial fluid. Sensitivity, specificity, negative predictive value, positive predictive value, and accuracy were determined. Patients were considered to have an infection if two of three criteria were met; the three criteria were a positive intraoperative culture, gross purulence at the time of reoperation, and positive histopathological findings. Thirty-four arthroplasties were excluded because of the presence of a draining sinus, incomplete data, or a preoperative diagnosis of inflammatory arthritis, leaving 201 total hip arthroplasties available for evaluation. Fifty-five hips were judged to be infected. No hip in a patient with a preoperative erythrocyte sedimentation rate of <30 mm/hr and a C-reactive protein level of <10 mg/dL was determined to be infected. Receiver-operating-characteristic curve analysis of the synovial fluid illustrated optimal cut-points to be >4200 white blood cells/mL for the white blood-cell count and >80% polymorphonuclear cells for the differential count. However, when combined with an elevated erythrocyte sedimentation rate and C-reactive protein level, the optimal cut-point for the synovial fluid cell count was >3000 white blood cells/mL, which yielded the highest combined sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the tests studied. A synovial fluid cell count of >3000 white blood cells/mL was the most predictive perioperative testing modality in our study for determining the presence of periprosthetic infection when combined with an elevated preoperative erythrocyte sedimentation rate and C-reactive protein level in patients undergoing revision total hip arthroplasty.
Extended Trochanteric Osteotomy
Elsevier eBooks, 2009
Journal of Arthroplasty, Apr 1, 2010
Intraprosthetic Dislocation of Dual-Mobility Bearings Associated with Closed Reduction
JBJS case connector, Mar 25, 2015
Case: We present two patients with dual-mobility total hip arthroplasty components who underwent ... more Case: We present two patients with dual-mobility total hip arthroplasty components who underwent closed reduction of posterior dislocations with conscious sedation in the emergency room. Following closed reduction, both patients had immediate pain, clicking, and grinding of the hip. Radiographs identified intraprosthetic dislocation of the dual-mobility components, and revision surgery was required. Conclusion: When dislocation of a dual-mobility bearing occurs, the surgeon should consider performing a careful closed reduction with muscle paralysis and use of fluoroscopic guidance in the operating room to avoid intraprosthetic dislocation.
Journal of Arthroplasty, Jun 1, 2005
Pelvic discontinuity is frequently encountered during acetabular revision in patients with severe... more Pelvic discontinuity is frequently encountered during acetabular revision in patients with severe acetabular bone loss. Prompt recognition of the discontinuity and appropriate intraoperative management are essential for a successful clinical outcome. The treatment of the discontinuity is dependent upon the remaining host bone, the potential for healing of the discontinuity, and the potential for biologic ingrowth of acetabular components. If healing potential of the discontinuity exists, the discontinuity should be treated in compression with a posterior column plate and structural allograft or with the use of trabecular metal acting as an internal plate. If healing potential for the discontinuity does not exist, the discontinuity can be bridged and treated in distraction with either an acetabular transplant supported with a cage or with the use of a custom Triflange implant. However, the poor clinical results observed with either of these treatment modalities for a type IIIB defect with an associated pelvic discontinuity have prompted the senior author to explore the use of a trabecular metal acetabular component with 1 or 2 augments in the majority of his current type IIIB cases. The long-term clinical results of this treatment remain unknown.
Journal of Arthroplasty, Oct 1, 2008
We investigated the early results of trabecular metal components in 23 acetabular revisions assoc... more We investigated the early results of trabecular metal components in 23 acetabular revisions associated with major bone loss. The mean age was 58.2 years. According to Paprosky's classification, there were 17 type IIIA and 6 type IIIB acetabular defects. Eight chronic pelvic discontinuities were intraoperatively assessed. No additional plating or bone grafting was necessary. The mean postoperative modified Postel-Merle d'Aubigne score was 10.6 points (8-12 points). The mean postoperative position of the center of rotation was 26.3 mm vertically (15-47 mm). The mean inclination was 45.1°(20°-63°). No mechanical failure occurred at a mean follow-up of 35 months (24-50 months). Trabecular metal components appear suitable to achieve primary stability in type III acetabular defect as an alternative to bone graft and cages.
Journal of Arthroplasty, Apr 1, 2010
Treatment of Severe Acetabular Deficiency Using Modular Trabecular Metal Components
Journal of Arthroplasty, Feb 1, 2007
Porous Metal Augments: Big Hopes for Big Holes
Orthopedics, Sep 7, 2010
The majority of acetabular defects can be reconstructed with a hemispherical acetabular component... more The majority of acetabular defects can be reconstructed with a hemispherical acetabular component alone. However, severe bone loss encountered at the time of revision acetabular surgery can result in compromised initial fixation leading to component micromotion, failure of bone ingrowth, and mechanical failure. Porous acetabular augments offer a potential solution to enhance initial component fixation while maximizing the area for biologic ingrowth. Premanufactured metal augments can be placed independent of the acetabular component. This feature provides surgeons the flexibility to place the hemispherical acetabular component in the optimal orientation at the anatomic hip center. The augment is initially secured to the hemipelvis with multiple screws before it is then secured to the hemispherical acetabular component with the use of polymethylmethacrylate bone cement. The modularity of the augments effectively allows a custom implant to be designed intraoperatively. Porous acetabular augments offer the potential advantages of a nonresorbable material that can be inserted without extensive soft tissue stripping. Additionally, these metal augments do not carry the risk of disease transmission associated with bulk structural allograft and are manufactured in a variety of shapes and sizes. The early clinical and radiographic results of porous acetabular augments are promising, yet there remains a paucity of long-term data.
Journal of the American Academy of Orthopaedic Surgeons, Apr 15, 2018
Background: Radiostereometric analysis (RSA) accurately assesses arthroplasty implant performance... more Background: Radiostereometric analysis (RSA) accurately assesses arthroplasty implant performance and is routinely used for research purposes. Because of its efficacy in detecting implant failure in research subjects, we deployed the use of RSA beads for routine surveillance in all elective total hip and total knee arthroplasty patients. Methods: We retrospectively compared 143 patients who received RSA beads intraoperatively with 343 patients who did not receive RSA beads. Using RSA images, we assessed bead stability at 6 weeks and 1 year postoperatively. Results: There were no intraoperative complications in the RSA group and two in the control group. No differences were found between groups for the surgical time and the expected blood loss. At 6 weeks, 99.5% of beads were considered to be stable, with stability increasing to 99.7% of beads at 1 year. The routine use of RSA bead insertion is a safe procedure and may provide the ability to assess implant fixation in clinical practice.
Arthroplasty today, Dec 1, 2017
Background: There is a paucity of data to guide management of the patella in revision total knee ... more Background: There is a paucity of data to guide management of the patella in revision total knee arthroplasty (RTKA). The purpose of this study was to review our experience with patellar management in RTKA. Methods: We retrospectively reviewed 422 consecutive RTKAs at a minimum of 2 years (mean, 42 months). Patellar management was guided by a classification that considered stability, size, and position of the implanted patellar component, thickness/quality of remaining bone stock, and extensor mechanism competence. Results: Management in 304 aseptic revisions included retention of a well-fixed component in 212 (69.7%) and revision using an all-polyethylene component in 46 (15.1%). Patella-related complications included 5 extensor mechanism ruptures (1.6%), 3 cases of patellar maltracking (1.0%), and 2 periprosthetic patellar fractures (0.7%). Of 118 2-stage revisions for infection, an all-polyethylene component was used in 88 (74.6%), patelloplasty in 20 (16.9%), and patellectomy in 7 (5.9%). Patella-related complications included 4 cases of patellar maltracking (3.4%), 3 extensor mechanism ruptures (2.5%), and 1 periprosthetic patellar fracture (0.8%). Conclusions: Septic revisions required concomitant lateral releases more frequently (38.1% vs 10.9%; P < .02) but had a similar rate of patellar complications (6.8% vs 3.3%; P ¼ .40). No cases required rerevision specifically for failure of the patellar component. Patients who had a patelloplasty had worse postoperative Knee Society functional scores than those with a retained or revised patellar component. In most aseptic RTKAs, a well-fixed patellar component can be retained. If revision is required, a standard polyethylene component is sufficient in most septic and aseptic revisions. Rerevisions related to the patellar component are infrequent.
(iii) Cementless femoral revision: The role of monoblock versus modular stems
Current Orthopaedics, Jun 1, 2006
ABSTRACT
Journal of Arthroplasty, Jun 1, 2010
Vascular injury is a rare but devastating complication of total hip arthroplasty. We present 2 ca... more Vascular injury is a rare but devastating complication of total hip arthroplasty. We present 2 cases of external iliac artery injury that complicated the removal of a chronically infected total hip arthroplasty where the acetabular component had migrated medial to Kohler's line. In both cases, hemostasis and reperfusion were achieved with the assistance of a vascular surgeon. This report describes the diagnosis, treatment, and associated risk factors for this rare complication. The combination of deep infection and medial migration of the acetabular component represents a high-risk situation for vascular injury. We advocate preoperative consultation with a vascular surgeon in this setting.
Journal of Bone and Joint Surgery, American Volume, Apr 1, 2005
The bone & joint journal, Jul 1, 2018
The aim of this study was to examine the results of the acetabular distraction technique in achie... more The aim of this study was to examine the results of the acetabular distraction technique in achieving implantation of a stable construct, obtaining biological fixation, and producing healing of chronic pelvic discontinuity at revision total hip arthroplasty. We identified 32 patients treated between 2006 and 2013 who underwent acetabular revision for a chronic pelvic discontinuity using acetabular distraction, and who were radiographically evaluated at a mean of 62 months (25 to 160). Of these patients, 28 (87.5%) were female. The mean age at the time of revision was 67 years (44 to 86). The patients represented a continuous series drawn from two institutions that adhered to an identical operative technique. Of the 32 patients, one patient required a revision for aseptic loosening, two patients had evidence of radiographic loosening but were not revised, and three patients had migration of the acetabular component into a more stable configuration. Radiographically, 22 (69%) of the cohort demonstrated healing of the discontinuity. The Kaplan-Meier construct survivorship was 83.3% when using revision for aseptic acetabular loosening as an endpoint. At the time when one patient failed due to aseptic loosening (at 7.4 years), there were a total of seven patients with a follow-up of seven years or longer who were at risk of failure. The acetabular distraction technique demonstrates encouraging radiographic outcomes, with healing of the discontinuity in over two-thirds of our series. This surgical technique permits biological fixation and intraoperative customization of the construct to be implanted based on the pattern of the bone loss identified following component removal.
Nephrotoxicity After the Treatment of Periprosthetic Joint Infection With Antibiotic-Loaded Cement Spacers
Journal of Arthroplasty, Jul 1, 2018
Treatment of periprosthetic joint infections commonly involves insertion of an antibiotic-loaded ... more Treatment of periprosthetic joint infections commonly involves insertion of an antibiotic-loaded cement spacer (ACS). The risk for acute kidney injury (AKI) related to use of antibiotic spacers has not been well defined. We aimed to identify the incidence of and risk factors for AKI after placement of an ACS. We performed a prospective cohort study of patients with an infected primary total hip or knee arthroplasty treated with ACSs with vancomycin, gentamicin, and tobramycin. Serum creatinine and glomerular filtration rate data were collected at baseline and weekly intervals for 8 weeks. Patients were classified into Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease (RIFLE) stages to determine incidence of AKI. Risk factors for kidney injury were identified via regression analysis. A total of 37 patients (20 total knee arthroplasty and 17 total hip arthroplasty) were included. During the 8 weeks after ACS placement, 10 patients (27%) fit RIFLE criteria for kidney injury and 2 patients (5%) fit RIFLE criteria for kidney failure. No baseline patient characteristics were associated with development of AKI. Patients should be monitored closely for development of AKI after placement of ACSs for the treatment of periprosthetic joint infection. Further research into minimizing risk for AKI is warranted.
Postoperative Pain Management After Primary Total Knee Arthroplasty: The Value of Liposomal Bupivacaine
Journal of Arthroplasty, Nov 1, 2016
Multimodal pain protocols have been proposed to achieve improved long-acting postoperative analge... more Multimodal pain protocols have been proposed to achieve improved long-acting postoperative analgesia. Controlling postoperative pain after joint arthroplasty is especially important as it relates to patient satisfaction and outcomes. The purpose of this study was to compare the postoperative pain, time to ambulation, and overall narcotic usage between patients who received either a femoral nerve block with a periarticular bupivacaine injection or a periarticular bupivacaine and extended-release liposomal bupivacaine injection after primary total knee arthroplasty. A total of 597 consecutive primary total knee arthroplasties performed between September 1, 2012 and August 31, 2014 received preoperative celecoxib, oxycodone, and transdermal scopolamine. Intraoperatively, patients either received a single-dose bupivacaine femoral nerve block along with 30-mL 0.25% bupivacaine periarticular injection (group A) or a 60-mL periarticular injection alone (20-mL liposomal bupivacaine, 30-mL 0.25% bupivacaine, and 10-mL saline; group B). The postoperative pain scores, narcotic usage, and time to ambulation were retrospectively collected from the electronic medical record. These outcomes were compared between treatment groups. There were 325 patients in group A compared with 272 in group B during the time frame. There was no difference among age, gender, race, and body mass index between the groups. Group B demonstrated a decreased need for breakthrough pain medication (16.9% vs 36.3% P &amp;lt; .001), decreased pain 12 hours postoperatively (3.2 vs 3.6 P &amp;lt; .003), and an earlier time to ambulation (29.5 hours vs 32.2 hours, P &amp;lt; .017). There was no difference in hospital length of stay (2.8 vs 2.6 days, P = .123). On controlling for demographic factors, patients in group B were able to ambulate 2.3 hours earlier than those in group A (coefficient = -2.3, P = .049). Liposomal bupivacaine resulted in a decrease need for breakthrough pain medication, improved pain scores at 12 hours, and an earlier time to ambulation compared to a combined femoral nerve block and periarticular bupivacaine injection.
The bone & joint journal, Nov 1, 2014
A pelvic discontinuity occurs when the superior and inferior parts of the hemi-pelvis are no long... more A pelvic discontinuity occurs when the superior and inferior parts of the hemi-pelvis are no longer connected, which is difficult to manage when associated with a failed total hip replacement. Chronic pelvic discontinuity is found in 0.9% to 2.1% of hip revision cases with risk factors including severe pelvic bone loss, female gender, prior pelvic radiation and rheumatoid arthritis. Common treatment options include: pelvic plating with allograft, cage reconstruction, custom triflange implants, and porous tantalum implants with modular augments. The optimal technique is dependent upon the degree of the discontinuity, the amount of available bone stock and the likelihood of achieving stable healing between the two segments. A method of treating pelvic discontinuity using porous tantalum components with a distraction technique that achieves both initial stability and subsequent long-term biological fixation is described.
Revision Total Hip Arthroplasty
Clinical Orthopaedics and Related Research, Dec 1, 2003
Femoral revision with a 7-inch or 8-inch fully porous-coated stem may not provide reliable long-t... more Femoral revision with a 7-inch or 8-inch fully porous-coated stem may not provide reliable long-term results in patients with moderate bone loss. The purpose of this study was to evaluate the limits of fully porous-coated stems and to create a treatment algorithm for femoral deficiencies. Fifty-one patients with either a 10-inch or 9-inch calcar fully porous-coated stem, 10 patients with impaction bone grafting, and 10 patients with a modular tapered stem were evaluated at an average 4.2 years postoperatively. The mechanical failure rate among the 9-inch and 10-inch fully porous-coated stems was 0% in Type III B defects with femoral canals less than 19 mm (15 patients), 18% in Type IIIB defects with femoral canals greater than 19 mm (2 of 11 patients) and 37.5% in Type IV defects (three of eight patients). There were no mechanical failures observed among the bone packing or modular tapered stems. Patients with Type IIIB defects and a femoral canal less than 19 mm can be treated successfully with either a 10-inch or 9-inch calcar fully porous-coated stem. However, patients with Type IIIB defect and an endosteal canal greater than 19 mm or a Type IV defect require alternative methods of reconstruction such as a modular tapered stem or a bone packing procedure.
Clinical Orthopaedics and Related Research, Dec 1, 2004
Methods.-A case-control study was performed to identify risk factors for prosthetic joint infecti... more Methods.-A case-control study was performed to identify risk factors for prosthetic joint infections (PJI). Antibiograms of isolates associated with PJI were reviewed. Molecular typing of available MRSA isolates was done using pulsed field gel electrophoresis (PFGE). Nares cultures of health care workers who provided care to those orthopedic patients were obtained. Results.-Over a 13-month period (January 2003-January 2004), 9.5% of patients with prosthetic hip (THA) or knee (TKA) joint surgery developed PJI (7 TKA and 2 THA). The mean time to development of PJI was 20 days. Five infections were caused by CA-MRSA and 3 by methicillin-susceptible S aureus; one was culture negative. All CA-MRSA isolates had identical antibiograms (resistant to -lactams and erythromycin; susceptible to clindamycin, trimethoprim-sulfamethoxazole, rifampin, gentamicin, levofloxacin, and vancomycin). Molecular typing of 2 available CA-MRSA isolates revealed that these were the USA300 clone; these isolates were PVL+ and carried SCCmec IV. CA-MRSA was not recovered from nares cultures from 31 health care workers. In multivariate analysis, TKA (OR, 8.1; 95% CI: 1.3-48.1) and surgery time >180 minutes (OR, 7.4; 95% CI: 1.4-39.6) were associated with PJI. Conclusion.-We have demonstrated that the CA-MRSA USA300 clone is no longer just a cause of community-acquired infections but has also emerged as a cause of health care-associated infections, causing PJI at our institution.
Perioperative Testing for Joint Infection in Patients Undergoing Revision Total Hip Arthroplasty
Journal of Bone and Joint Surgery, American Volume, Sep 1, 2008
While multiple tests are used to determine the presence of infection at the site of a total hip a... more While multiple tests are used to determine the presence of infection at the site of a total hip arthroplasty, few studies have applied a consistent algorithm to determine the utility of the various tests that are available. The purpose of the present study was to evaluate the utility of commonly available tests for determining the presence of periprosthetic infection in patients undergoing revision total hip arthroplasty. Two hundred and thirty-five consecutive total hip arthroplasties in 220 patients were evaluated by one of two surgeons using a consistent algorithm to identify infection and were treated with reoperation. Receiver-operating-characteristic curve analysis was used to determine the optimal cut-point values for the white blood-cell count and the percentage of polymorphonuclear cells of intraoperatively aspirated hip synovial fluid. Sensitivity, specificity, negative predictive value, positive predictive value, and accuracy were determined. Patients were considered to have an infection if two of three criteria were met; the three criteria were a positive intraoperative culture, gross purulence at the time of reoperation, and positive histopathological findings. Thirty-four arthroplasties were excluded because of the presence of a draining sinus, incomplete data, or a preoperative diagnosis of inflammatory arthritis, leaving 201 total hip arthroplasties available for evaluation. Fifty-five hips were judged to be infected. No hip in a patient with a preoperative erythrocyte sedimentation rate of &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;30 mm/hr and a C-reactive protein level of &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;10 mg/dL was determined to be infected. Receiver-operating-characteristic curve analysis of the synovial fluid illustrated optimal cut-points to be &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;4200 white blood cells/mL for the white blood-cell count and &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;80% polymorphonuclear cells for the differential count. However, when combined with an elevated erythrocyte sedimentation rate and C-reactive protein level, the optimal cut-point for the synovial fluid cell count was &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;3000 white blood cells/mL, which yielded the highest combined sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the tests studied. A synovial fluid cell count of &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;3000 white blood cells/mL was the most predictive perioperative testing modality in our study for determining the presence of periprosthetic infection when combined with an elevated preoperative erythrocyte sedimentation rate and C-reactive protein level in patients undergoing revision total hip arthroplasty.
Extended Trochanteric Osteotomy
Elsevier eBooks, 2009
Journal of Arthroplasty, Apr 1, 2010
Intraprosthetic Dislocation of Dual-Mobility Bearings Associated with Closed Reduction
JBJS case connector, Mar 25, 2015
Case: We present two patients with dual-mobility total hip arthroplasty components who underwent ... more Case: We present two patients with dual-mobility total hip arthroplasty components who underwent closed reduction of posterior dislocations with conscious sedation in the emergency room. Following closed reduction, both patients had immediate pain, clicking, and grinding of the hip. Radiographs identified intraprosthetic dislocation of the dual-mobility components, and revision surgery was required. Conclusion: When dislocation of a dual-mobility bearing occurs, the surgeon should consider performing a careful closed reduction with muscle paralysis and use of fluoroscopic guidance in the operating room to avoid intraprosthetic dislocation.
Journal of Arthroplasty, Jun 1, 2005
Pelvic discontinuity is frequently encountered during acetabular revision in patients with severe... more Pelvic discontinuity is frequently encountered during acetabular revision in patients with severe acetabular bone loss. Prompt recognition of the discontinuity and appropriate intraoperative management are essential for a successful clinical outcome. The treatment of the discontinuity is dependent upon the remaining host bone, the potential for healing of the discontinuity, and the potential for biologic ingrowth of acetabular components. If healing potential of the discontinuity exists, the discontinuity should be treated in compression with a posterior column plate and structural allograft or with the use of trabecular metal acting as an internal plate. If healing potential for the discontinuity does not exist, the discontinuity can be bridged and treated in distraction with either an acetabular transplant supported with a cage or with the use of a custom Triflange implant. However, the poor clinical results observed with either of these treatment modalities for a type IIIB defect with an associated pelvic discontinuity have prompted the senior author to explore the use of a trabecular metal acetabular component with 1 or 2 augments in the majority of his current type IIIB cases. The long-term clinical results of this treatment remain unknown.
Journal of Arthroplasty, Oct 1, 2008
We investigated the early results of trabecular metal components in 23 acetabular revisions assoc... more We investigated the early results of trabecular metal components in 23 acetabular revisions associated with major bone loss. The mean age was 58.2 years. According to Paprosky's classification, there were 17 type IIIA and 6 type IIIB acetabular defects. Eight chronic pelvic discontinuities were intraoperatively assessed. No additional plating or bone grafting was necessary. The mean postoperative modified Postel-Merle d'Aubigne score was 10.6 points (8-12 points). The mean postoperative position of the center of rotation was 26.3 mm vertically (15-47 mm). The mean inclination was 45.1°(20°-63°). No mechanical failure occurred at a mean follow-up of 35 months (24-50 months). Trabecular metal components appear suitable to achieve primary stability in type III acetabular defect as an alternative to bone graft and cages.
Journal of Arthroplasty, Apr 1, 2010
Treatment of Severe Acetabular Deficiency Using Modular Trabecular Metal Components
Journal of Arthroplasty, Feb 1, 2007
Porous Metal Augments: Big Hopes for Big Holes
Orthopedics, Sep 7, 2010
The majority of acetabular defects can be reconstructed with a hemispherical acetabular component... more The majority of acetabular defects can be reconstructed with a hemispherical acetabular component alone. However, severe bone loss encountered at the time of revision acetabular surgery can result in compromised initial fixation leading to component micromotion, failure of bone ingrowth, and mechanical failure. Porous acetabular augments offer a potential solution to enhance initial component fixation while maximizing the area for biologic ingrowth. Premanufactured metal augments can be placed independent of the acetabular component. This feature provides surgeons the flexibility to place the hemispherical acetabular component in the optimal orientation at the anatomic hip center. The augment is initially secured to the hemipelvis with multiple screws before it is then secured to the hemispherical acetabular component with the use of polymethylmethacrylate bone cement. The modularity of the augments effectively allows a custom implant to be designed intraoperatively. Porous acetabular augments offer the potential advantages of a nonresorbable material that can be inserted without extensive soft tissue stripping. Additionally, these metal augments do not carry the risk of disease transmission associated with bulk structural allograft and are manufactured in a variety of shapes and sizes. The early clinical and radiographic results of porous acetabular augments are promising, yet there remains a paucity of long-term data.
Journal of the American Academy of Orthopaedic Surgeons, Apr 15, 2018
Background: Radiostereometric analysis (RSA) accurately assesses arthroplasty implant performance... more Background: Radiostereometric analysis (RSA) accurately assesses arthroplasty implant performance and is routinely used for research purposes. Because of its efficacy in detecting implant failure in research subjects, we deployed the use of RSA beads for routine surveillance in all elective total hip and total knee arthroplasty patients. Methods: We retrospectively compared 143 patients who received RSA beads intraoperatively with 343 patients who did not receive RSA beads. Using RSA images, we assessed bead stability at 6 weeks and 1 year postoperatively. Results: There were no intraoperative complications in the RSA group and two in the control group. No differences were found between groups for the surgical time and the expected blood loss. At 6 weeks, 99.5% of beads were considered to be stable, with stability increasing to 99.7% of beads at 1 year. The routine use of RSA bead insertion is a safe procedure and may provide the ability to assess implant fixation in clinical practice.
Arthroplasty today, Dec 1, 2017
Background: There is a paucity of data to guide management of the patella in revision total knee ... more Background: There is a paucity of data to guide management of the patella in revision total knee arthroplasty (RTKA). The purpose of this study was to review our experience with patellar management in RTKA. Methods: We retrospectively reviewed 422 consecutive RTKAs at a minimum of 2 years (mean, 42 months). Patellar management was guided by a classification that considered stability, size, and position of the implanted patellar component, thickness/quality of remaining bone stock, and extensor mechanism competence. Results: Management in 304 aseptic revisions included retention of a well-fixed component in 212 (69.7%) and revision using an all-polyethylene component in 46 (15.1%). Patella-related complications included 5 extensor mechanism ruptures (1.6%), 3 cases of patellar maltracking (1.0%), and 2 periprosthetic patellar fractures (0.7%). Of 118 2-stage revisions for infection, an all-polyethylene component was used in 88 (74.6%), patelloplasty in 20 (16.9%), and patellectomy in 7 (5.9%). Patella-related complications included 4 cases of patellar maltracking (3.4%), 3 extensor mechanism ruptures (2.5%), and 1 periprosthetic patellar fracture (0.8%). Conclusions: Septic revisions required concomitant lateral releases more frequently (38.1% vs 10.9%; P < .02) but had a similar rate of patellar complications (6.8% vs 3.3%; P ¼ .40). No cases required rerevision specifically for failure of the patellar component. Patients who had a patelloplasty had worse postoperative Knee Society functional scores than those with a retained or revised patellar component. In most aseptic RTKAs, a well-fixed patellar component can be retained. If revision is required, a standard polyethylene component is sufficient in most septic and aseptic revisions. Rerevisions related to the patellar component are infrequent.