Henry D. Clarke

Surgical Treatment of Early Wound Complications Following Primary Total Knee Arthroplasty

BACKGROUND Wound-healing problems are a known complication after primary total knee arthroplasty. However, little is known about the clinical outcomes for patients who require surgical treatment of these early wound-healing problems. The purpose of the present study was to determine the incidence, risk factors, and long-term sequelae of early wound complications requiring surgical treatment. METHODS The total joint registry at our institution was reviewed for the period from 1981 to 2004. All knees with early wound complications necessitating surgical treatment within thirty days after the index total knee arthroplasty were identified. The cumulative probabilities for the later development of deep infection and major subsequent surgery were determined. A case-control study in which these patients were matched with an equal number of controls was performed to attempt to identify risk factors for the development of early superficial wound complications requiring surgical intervention. RESULTS From 1981 to 2004, 17,784 primary total knee arthroplasties were performed at our institution. Fifty-nine knees were identified as having early wound complications necessitating surgical treatment within thirty days after the index arthroplasty, for a rate of return to surgery of 0.33%. For knees with early surgical treatment of wound complications, the two-year cumulative probabilities of major subsequent surgery (component resection, muscle flap coverage, or amputation) and deep infection were 5.3% and 6.0%, respectively. In contrast, for knees without early surgical intervention for the treatment of wound complications, the two-year cumulative probabilities were 0.6% and 0.8%, respectively (p < 0.001 for both comparisons). A history of diabetes mellitus was identified as being significantly associated with the development of early wound complications requiring surgical intervention. CONCLUSIONS Patients requiring early surgical treatment for wound-healing problems after primary total knee arthroplasty are at significantly increased risk for further complications, including deep infection and/or major subsequent surgery, specifically, resection arthroplasty, amputation, or muscle flap coverage. These results emphasize the importance of obtaining primary wound-healing after total knee arthroplasty.

Minimal-incision total knee arthroplasty: The early clinical experience

Minimal-incision total knee arthroplasty can be considered part of the continuum from traditional extensile exposures to the quadriceps-sparing approach. We did this study to identify preoperative variables that predict which patients are amenable to a mini-incision and mini-arthrotomy technique, and to compare early outcomes in these patients versus patients in whom a standard approach was required. A consecutive series of 118 primary total knee arthroplasties were evaluated. In each case, the incision and arthrotomy were kept as small as possible, while still allowing proper implantation of the prosthesis. Group 1 consisted of 69 patients (58%) with skin incisions smaller than 14 cm and limited medial parapatellar arthrotomies. Group 2 consisted of 49 patients (42%) with incisions greater than or equal to 14 cm and standard medial parapatellar arthrotomies. Patients in Group 1 averaged one size smaller femoral and tibial components, had narrower femurs, required fewer transfusions and had better postoperative flexion. There were no differences between the groups in length of hospital stay, ambulatory ability, stair-climbing, tourniquet time, radiographic alignment, or complications. Based on these results, the ideal patient for a minimal incision total knee arthroplasty and limited arthrotomy seems to be a thin woman with a low body mass index, a narrow femur, and good preoperative range of motion. Level of Evidence: Prognostic study, Level III-1 (retrospective cohort study). See the Guidelines for Authors for a complete description of levels of evidence.

The Alpha Defensin-1 Biomarker Assay can be Used to Evaluate the Potentially Infected Total Joint Arthroplasty

BackgroundDiagnosing a periprosthetic joint infection (PJI) requires a complex approach using various laboratory and clinical criteria. A novel approach to diagnosing these infections uses synovial fluid biomarkers. Alpha defensin-1 (AD-1) is one such synovial-fluid biomarker. However little is known about the performance of the AD-1 assay in the diagnosis of PJI.Questions/purposesWe sought to (1) determine the sensitivity and specificity of the AD-1 assay in a population of patients being evaluated for PJI, using the Musculoskeletal Infection Society (MSIS) criteria as the reference standard, and (2) compare the AD-1 assay with other currently available clinical tests, specifically cell count, culture, erythrocyte sedimentation rate, and C-reactive protein.Patients and MethodsA retrospective review was performed of all patients undergoing workup for a PJI at our institution from January to June 2013. Sixty-one AD-1 assays were done in 57 patients. The group included 51 patients with 55 painful joints and six patients who underwent aspiration before second-stage reimplantation. Patients were considered to have a PJI if they met the MSIS criteria. We calculated the sensitivity and specificity of the AD-1 synovial fluid assay, and compared it with the sensitivity and specificity of the synovial fluid cell count, culture, erythrocyte sedimentation rate, and C-reactive protein. There were 19 diagnosed infections in the 61 aspirations, with 21 positive and 40 negative AD-1 assays. There were two false positive and no false negatives AD-1 assays.ResultsThe sensitivity and specificity for the AD-1 assay were 100% (95% CI, 79%–100%) and 95% (95% CI, 83%–99%), respectively. The sensitivity and specificity of the other tests ranged from 68% to 95% and 66% to 88%, respectively. The AD-1 assay results outperformed the other tests but did not reach statistical significance except for the sensitivity of the erythrocyte sedimentation rate.ConclusionThe sensitivity and specificity of the synovial fluid AD-1 assay exceeded the sensitivity and specificity of the other currently available clinical tests evaluated here but did not reach significance. The AD-1 assay offers another test with high sensitivity and specificity for diagnosing a PJI especially in the case where the diagnosis of PJI is uncertain, but larger studies will be needed to determine significance and cost effectiveness.Level of EvidenceLevel III, diagnostic study. See the Instructions for Authors for a complete description of levels of evidence.

Early Return to Surgery for Evacuation of a Postoperative Hematoma After Primary Total Knee Arthroplasty

BACKGROUND Development of a postoperative hematoma is a reported complication after primary total knee arthroplasty. However, little is known about the clinical outcomes in patients who require surgical evacuation of an acute hematoma. The purpose of this study was to determine the incidence, risk factors, and long-term sequelae of postoperative hematomas requiring surgical evacuation. METHODS From 1981 to 2004, 17,784 primary total knee arthroplasties were performed at our institution. Forty-two patients (forty-two knees) returned to the operating room within thirty days of the index arthroplasty for evacuation of a postoperative hematoma. A case-control study, with forty-two patients matched one-to-one with forty-two control subjects, was performed to attempt to identify risk factors for the development of postoperative hematoma requiring surgical evacuation. RESULTS The rate of return to surgery within thirty days for evacuation of a postoperative hematoma was 0.24% (95% confidence interval, 0.17% to 0.32%). For patients undergoing postoperative hematoma evacuation, the two-year cumulative probabilities of undergoing subsequent major surgery (component resection, muscle flap coverage, or amputation) or having a deep infection develop were 12.3% (95% confidence interval, 1.6% to 22.4%) and 10.5% (95% confidence interval, 0.2% to 20.2%), respectively. In contrast, for knees without early hematoma evacuation, the two-year cumulative probabilities were 0.6% (95% confidence interval, 0.5% to 0.7%) and 0.8% (95% confidence interval, 0.6% to 0.9%), respectively (p < 0.001 for both outcomes). A history of a bleeding disorder was identified as having a significant association with the development of a hematoma requiring surgical evacuation (p = 0.046). CONCLUSIONS Patients who return to the operating room within thirty days after the index total knee arthroplasty for evacuation of a postoperative hematoma are at significantly increased risk for the development of deep infection and/or undergoing subsequent major surgery. These results support all efforts to minimize the risk of postoperative hematoma formation.

Restoration of femoral anatomy in TKA with unisex and gender-specific components

Recent modifications in total knee prosthesis design theoretically better accommodate the anatomy of the female femur and thereby have the theoretical potential to improve clinical results in TKA by more accurately restoring femoral posterior condylar offset, reducing femoral notching, reducing femoral component flexion, and reducing component overhang. First, we radiographically evaluated whether a contemporary unisex prosthesis would accommodate female anatomy equally as well as male anatomy. Next, we radiographically evaluated female knees in which a gender-specific prosthesis was used. Pre- and postoperative radiographs of 122 knees (42 female unisex, 41 male unisex, 39 female gender-specific) were reviewed. In the unisex groups, there were no differences in femoral notching or femoral component flexion. Posterior femoral offset increased in both groups. However, femoral component overhang was worse in female knees (17%) than in male knees (0%). In the gender-specific female group, the incidence of component overhang was similar to that in the unisex female group. Unisex femoral components of this specific design do not equally match the native anatomy male and female knees. In some women, a compromise was required in sizing.

Blood Management in Total Knee Arthroplasty: A Comparison of Techniques

Patients undergoing total knee arthroplasty (TKA) are at high risk for postoperative anemia and allogeneic blood transfusions. Risks associated with allogeneic blood exposure (ie, infection, fluid overload, and longer hospital stays) have prompted alternative blood management strategies. The main goal of this study was to evaluate whether a single change in the clinical blood management of patients undergoing TKA reduced the severity of postoperative anemia or the need for allogeneic blood transfusions. A second goal of this study was to assess the financial impact of the change on the institution. This study compared perioperative cell salvage, preoperative autologous blood donation, and the practice of using allogeneic blood alone in patients undergoing TKA. Clinical and financial data of 154 unique cases of primary TKA at the Mayo Clinic Arizona were retrospectively reviewed. Transfusion rates were 25%, 18%, and 52% respectively for patients in the cell salvage, preoperative autologous blood donation, and allogeneic blood only groups. Respective relative risk reductions were 51.9% (P=.007) and 65.4% (P=.002) with the use of cell salvage or preoperative autologous blood donation versus allogeneic alone. Cell salvage and preoperative autologous blood donation were found to significantly reduce the requirements for allogeneic blood transfusions; these techniques were found to be roughly equivalent in clinical benefit when compared to the use of allogeneic blood alone. The logistical advantages of cell salvage (ie, no preoperative blood donation, no risk of wasting blood units) were associated with greater costs to the institution.

Salvage of failed femoral megaprostheses with allograft prosthesis composites.

The records of 11 consecutive adult patients who underwent revision of a failed femoral megaprosthesis (aseptic loosening, nine; periprosthetic fracture, one; and prosthesis fracture, one) to an allograft prosthesis composite were reviewed retrospectively. Complications included radiographic component subsidence in two patients (18%), hip instability in three patients (27%), deep infection in two patients (18%), and allograft fractures in two patients (18%). Five patients (45%) required subsequent reoperations; four patients underwent removal of the allograft prosthesis composite at a mean of 16 months (range, 5-41 months) and one patient (9%) with hip instability underwent revision of the failed megaprosthesis to a constrained acetabulum. Reconstruction of a failed femoral megaprosthesis is a complex problem caused by extensive bone loss and violation of soft tissue attachments. Despite a high complication rate, six patients (55%) remained ambulatory and had mild or no pain at a mean followup exceeding 5.5 years.

Preoperative patient education reduces in-hospital falls after total knee arthroplasty.

BackgroundInpatient hospital falls after orthopaedic surgery represent a major problem, with rates of about one to three falls per 1000 patient days. These falls result in substantial morbidity for the patient and liability for the institution.Questions/purposesWe determined whether preoperative patient education reduced the rate of in-hospital falls after primary TKA and documented the circumstances and the injuries resulting from the falls.Patients and MethodsWe reviewed data from all 244 patients who underwent primary TKA at a single institution between March and November 2009. Seventy-two patients of one surgeon were enrolled in a preoperative nurse-led education program. This group was compared with a control group of 172 patients who concurrently underwent TKA at the same institution but did not receive preoperative education.ResultsMore control patients had in-hospital falls than those in the education group: seven (one of whom had two falls) of 172 (4%) versus none of 72 (0%), respectively. Three of the eight falls resulted in a serious injury, including one wound dehiscence and one wound hematoma that both required repeat surgery and one clavicle fracture.ConclusionsInpatient falls after TKA may be associated with major complications. Our preoperative patient education reduced these falls and is now mandatory for patients undergoing TKA at our institution.Level of EvidenceLevel III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Primary Total Knee Arthroplasty

• Understand correction of fixed deformity in primary total knee arthroplasty via the harmonization of osseous resection and soft-tissue balance • Understand the pitfalls in the surgical technique of balancing a total knee prosthesis.

The painful total knee arthroplasty: diagnosis and management.

The results of TKA during the past two decades have been reliable and favorable. While success rates are high, some patients experience pain and impaired function. This clinical scenario can be frustrating to both the patient and the surgeon who is accustomed to good outcomes. A systematic evaluation of the patient and arthroplasty can lead to a definitive diagnosis of the cause of the patients symptoms. Problems can be caused by a broad spectrum of possible etiologies. It is helpful to divide the differential diagnosis into two broad categories: extra-articular and intra-articular etiologies. When trying to establish the diagnosis, it is important to approach the task in a systematic fashion. Evaluation must begin with a thorough history and physical examination. Laboratory tests and imaging studies can provide additional evidence supporting a particular diagnosis. Once the etiology has been established, symptomatic relief may be achieved with appropriate treatment including revision TKA. However, revision TKA that is performed for unexplained pain is associated with a low probability of success.