Acetabular defect management and revision arthroplasty via the direct anterior approach.

OBJECTIVE: Acetabular revision arthroplasty and osseous defect management through the direct anterior approach (DAA) with or without proximal extension. INDICATIONS: Aseptic or septic component loosening, periacetabular osseous defects, pelvic discontinuity, intrapelvic cup protrusion, anterior pseudotumors, iliopsoas tendonitis, polyethylene wear or iliopsoas abscess. CONTRAINDICATIONS: Clinically relevant gluteal tendon lesions, active infection, morbid obesity, large abdominal pannus, ASA (American Society of Anesthesiologists) score > III, inguinal skin infection. SURGICAL TECHNIQUE: Electrocautery dissection is recommended to dissect the Hueter interval and to debulk pericapsular scar tissue. At all times during capsular debulking, it should be made sure not to damage the iliopsoas tendon or the neurovascular bundle. A stepwise releasing sequence can facilitate dislocation of the prosthesis. Most cases can be revised via the standard DAA but certain circumstances require an intra- or extrapelvic extension. Access to the anterior gluteal surface of the ilium can be provided using a "tensor snip". More posterior access is provided by the extensile extrapelvic approach described by Smith-Petersen. The intrapelvic Levine extension offers access to the entire visceral surface of the ilium and large parts of the anterior column. POSTOPERATIVE MANAGEMENT: Patient revised via the intra- or extrapelvic extension and patients suffering from extensive soft tissue or osseous defects should undergo postoperative weight-bearing restrictions with 20 kg for 6 weeks. RESULTS: Based on our studies, there is no limitation on the type of acetabular implant that can be used in DAA revision arthroplasty. Moreover, virtually all types of periacetabular osseous defects can be managed through the approach and its extensions. Acetabular revision arthroplasty via the DAA and its extensions is safe and can result in good midterm results.

Direct anterior approach total hip arthroplasty with an orthopedic traction table.

OBJECTIVE: Direct anterior approach total hip arthroplasty (DAA THA) has gained significant popularity in the last decade as it is a muscle-sparing procedure. Modern techniques for DAA THA utilize both a standard operating table and an orthopedic traction table. As the use of an orthopedic traction table shows technical ease and predictability, this article will focus on the use of the orthopedic table or table extension to facilitate DAA THA. INDICATIONS: Primary or secondary arthritis requiring THA; revision surgery-both acetabular and femoral. CONTRAINDICATIONS: Posterior wall hardware requiring removal; posterior mass (tumor) to be removed at surgery: large, overhanging pannus; need for gluteal tendon reconstruction; anterior skin envelope not conducive to DAA. SURGICAL TECHNIQUE: The incision is made over the tensor fascia latae. Capsulotomy is performed exposing the hip joint. After osteotomy of the femoral neck, traction is placed on the leg utilizing the orthopedic table and the head is removed. The acetabular cup is inserted. Traction, flexion, and internal reduction are used simultaneously while directing the femoral head into the acetabulum. RESULTS: In a meta-analysis, operative time (100 vs. 71 min), blood loss (531 vs. 382 ml), and intraoperative fracture rate (1.7 vs. 1.3%) were increased in the traction table cohort. All other complications and outcome measurements were the same. Traction-table related complications such as pudendal nerve palsy and ankle fractures were not found. An assessment of the senior author's initial 855 DAA THAs (2008-2014) showed a mean operative time of 65 min with a mean blood loss of 238 ml. Operative times decreased to average 56 min. Intraoperative fracture rate was 0.8%. Infection rate was 2.1%. Finally, 1.5% femoral implants did not osseointegrate and required revision after an average of 3.0 years.

Factors associated with pain intensity and magnitude of limitations among people with hip and knee arthritis.

BACKGROUND: The pain and limitations associated with osteoarthritis of the hip and knee have a notable variation that does not correspond directly with pathophysiology. The purpose of this study is to assess the influence of location of the arthritis on pain intensity and magnitude of limitations accounting for personal and psychological factors. METHODS: One hundred and fifty four patients with osteoarthritis of the hip (41 patients) or the knee (113 patients) were enrolled in this prospective cross sectional cohort study. Patients answered questionnaires which included demographics, site of arthritis (hip or knee), laterality (unilateral or bilateral), pain intensity, Patient-Reported Outcomes Measurement Information System Physical Function Computer Adaptive Test (PROMIS PF CAT), and psychologic questionnaires including the Tampa Scale of Kinesiophobia (TSK-4), Pain Catastrophizing Scale (PCS-4), Generalized Anxiety Disorder (GAD-2) and Patient-Reported Outcomes Measurement Information System Depression Computer Adaptive Test (PROMIS Dep CAT). Kellgren-Lawrence classification was classified by the treating surgeon. Associations of these factors with pain and function were assessed using bivariate and multivariable regression models. RESULTS: In a multivariable model accounting for potential confounding, magnitude of limitations was independently associated with years of education, work status, time spent exercising, catastrophic thinking (PCS-4), and symptoms of depression. They accounted for 50% of variability in physical function, with the major contributor being catastrophic thinking. The model for pain intensity included time spent exercising and fear of painful movement (TSK-4). Anatomic site and radiographic severity of arthritis were not associated with either physical function or pain in our patient sample. CONCLUSIONS: This study confirms that limitations and pain from osteoarthritis of the hip and knee are more closely related to personal and psychological factors, less effective cognitive coping strategies such as catastrophic thinking and kinesiophobia in particular, than to pathological and anatomical factors such as location and severity of arthritis. Care that incorporates incremental correction of common misconceptions that accompany the nociception from osteoarthritis have the potential to improve function and comfort in people with osteoarthritis. LEVEL OF EVIDENCE: Prognostic Level II.

Safely Implementing the Direct Anterior Total Hip Arthroplasty: A Methodological Approach to Minimizing the Learning Curve.

INTRODUCTION: Orthopaedic surgeons often cite concern for a learning curve as a barrier to adopting the direct anterior approach (DAA) for total hip arthroplasty (THA) while transitioning from other approaches. Studies both assessing and describing a practical approach and strategy to safely accomplish this transition, as well as the effect on clinical outcomes, are not well described. METHODS: This prospective study compares a single surgeon's operative results and complications for the first consecutive 100 direct anterior THA to the last 100 consecutive posterior THA after 7 years in practice. The regimented and disciplined learning strategy used to implement the DAA is detailed in this study. The data were analyzed using univariate and multivariate regression models. RESULTS: Univariate analyses identified significant differences in sex, age, Asian race, and diagnostic cause for THA between the two cohorts. Multivariate analyses controlled for these differences and showed that relative to posterior THA, direct anterior THA cases were associated with 7-minute longer procedures (P = 0.002) and lengths of stay that were 0.7 days fewer (P = 0.013). No significant differences were present in the estimated blood loss, and importantly, no significant differences in death or surgical complication rates between cohorts. DISCUSSION: This study suggests that the DAA for THA can be safely implemented without the increased and adverse risk to the patient when a structured learning process is maintained and meticulously performed.

Logistical and Economic Advantages of Sterile-Packed, Single-Use Instruments for Total Knee Arthroplasty.

BACKGROUND: Total knee arthroplasty (TKA) is well established as a clinically successful and cost-effective procedure. The transition of the US healthcare system from a fee-for-service model to a value-based care model requires careful examination of patient care to ensure both quality and efficiency. Sterile-packed, single-use instruments have been introduced as a tool to help streamline the operating room (OR) logistics while reducing sterilization requirements. The aim of this study was to examine the potential logistic and economic benefits of single-use instruments compared to traditional, reusable instruments for TKA. METHODS: Four variables related to TKA costs and logistics were modeled in this study: OR turnover time tray sterilization, tray management time, and 90-day infection rates. Model input data for traditional instruments and single-use instruments were based on peer-reviewed literature. A total of 200 sites and 500 cases per site were simulated using the Monte-Carlo-Technique. RESULTS: The median total cost savings with single-use instruments was $994 per case. The largest driver for cost savings was tray sterilization. Sites with higher staff wages and sterilization costs had a larger probability of realizing greater cost savings with adoption of single-use instruments. In cases using single-use instruments, up to 51% of operating days could have accommodated an additional procedure due to the time savings in OR turnover. CONCLUSION: This cost modeling study observed significant potential for logistical and economic improvements in TKA with single-use vs reusable instruments. Although few studies have been conducted to measure the impact of single-use instruments in practice, the results of these simulations motivate further investigation.

Anthropometric measurements of the femur change with component positioning in total knee arthroplasty.

BACKGROUND: To analyze aspect ratio (AP size/ (ML) size) of osteoarthritic knees at four different areas of the femur and to observe if proximalization of the femoral cut would change the ML size as well as confirm that external rotation increases the measurements for the AP dimensions of the femur. METHOD: From the available MyKnee database (Medacta International, Castel San Pietro, Switzerland) 1030 patients were randomly selected within 20° of deformity consisting of 400 men with a mean (SD) age of 67.5 (9) years and 630 women with a mean (SD) age of 69 (10) years (p<0.0001). A specific software program was developed to measure AP and ML dimensions of the femur on CT-scans for (3D) planning in four areas. The AP femoral size was measured with neutral axial rotation following the epicondylar axis and without accepting anterolateral notching. RESULTS: Proximalization of the femur resulted in no changes except for a larger ML3 area in men. Increased axial rotation increased the AP dimensions for the same femur by a mean (SD) 2.5 (1) mm for males and females. CONCLUSIONS: The crucial area for overhang of the femoral component is the anterior region (ML1) with an aspect ratio of about ±, but with an important range. Proximalization of the femoral cut is not accompanied by narrowing of the anterior femur but ML widening of the more posterior femur in men. Increased external rotation leads to a measurement of bigger AP size leading to an AP versus ML mismatch and change in aspect ratio.

Improving follow-up of indigent patients enrolled in medical research studies: a review of two studies in which 100% follow-up was obtained.

Follow-up of indigent patients is difficult. Demographics collected at initial hospitalization change often and are unreliable. In a boxer fracture study, at 1-year follow-up, 3 out of 100 patients were available. This poor performance prompted investigation of new methods for intake/ongoing care. A direct comparison of two studies was conducted. In study 1, demographics were obtained per standard hospital procedure. Patients were paid $50.00 per visit as an incentive. In study 2, expanded demographics were gathered. Related contacts were identified and credibility was verified. Rapport was established with the patient and family. In both studies, 100% follow-up was obtained. Significant difficulty was experienced obtaining follow-up in study 1. Patients attempted to renegotiate compensation. Follow-up was perceived as unnecessary and unpleasant. Study 2 patients kept appointments, expressed comfort during follow-up, and felt part of the treatment team. In both cases, availability of patients for follow-up increased dramatically. Financial compensation was troublesome. Providing access to an interested medical team was less cumbersome and provided superior results.

Surface cementation of stemmed tibial components in primary total knee arthroplasty: minimum 5-year follow-up.

Cement remains the "gold standard" for fixation in total knee arthroplasty. Between 1991 and 1998, 128 consecutive knees in 109 patients underwent primary cemented total knee arthroplasty using a surface cementation technique. The average follow-up was 95 (range, 63-155) months. Preoperative range of motion (ROM) averaged 5 degrees to 111 degrees which improved to 1 degrees to 116 degrees postoperatively. Modified Hospital for special surgery score (HSS) scores improved from 61 (range, 47-76) to 97 (range, 81-100) and the corresponding Knee Society Scores from 122 (range, 94-152) to 195 (range, 162-200). No osteolytic lesions were found; however, 3 tibias had radiolucent lines which were asymptomatic, nonprogressive, and not associated with implant failure. The average depth of penetration of cement was 2.7 mm. One knee (1%) required revision surgery for femoral loosening, and 1 required revision of the polyethylene liner. The present cementation technique provides excellent durable results at midterm follow-up.

Ten-year experience using an articulating antibiotic cement hip spacer for the treatment of chronically infected total hip.

Infection is a devastating complication after total-hip arthroplasty. Between June 1991 and December 2001, 42 patients were treated at our center for chronically infected total-hip arthroplasty using a 2-stage articulating antibiotic hip spacer technique. Of the 27 patients available for review, 26 (94%) remain clinically free of infection at an average 76 months (range, 28-148 months) postoperatively. Twenty-two (81%) patients had a positive identification of the infecting organism. All patients received a minimum of 6 weeks of intravenous antibiotics and the Harris Hip Scores improved from 53 (range, 36-68) to 92 (range, 81-99) postoperatively. Advantages of this technique include improved patient function, maintenance of bone stock and soft tissue tension, thus simplifying reimplantation.

Treatment of infected total knee arthroplasty using an articulating spacer: 2- to 12-year experience.

UNLABELLED: Fifty consecutive patients with late infected total knee arthroplasties were treated by debridement and removal of all components and cement, preserving the collateral ligaments. At the time of debridement, an articulating spacer was made to allow partial weightbearing and range of motion of the knee during rehabilitation. This spacer was implanted using antibiotic-impregnated bone cement. For this purpose, 4.8 g powdered tobramycin was mixed with 40 g Simplex cement. Cement was applied early to the components, but applied late to the femur, tibia, and patella to allow molding to the defects and bone without adherence to bone. Patients had tailored intravenous antibiotic therapy for 6 weeks for treatment of various gram-positive and gram-negative organisms. All patients had cemented revision total knee arthroplasty using antibiotic-impregnated cement with standard cementing techniques. Range of motion before reimplantation was 6 degrees -91 degrees . Followup averaged 73 months (range, 24-150 months). The average modified Hospital for Special Surgery knee score after revision was 89 points (range, 70-100 points) with 90% good to excellent results, excluding the results of patients with reinfection. Range of motion after reimplantation was 4 degrees -104 degrees. Six patients had recurrences of infection, and one patient with a poor postoperative range of motion had a fusion. Use of an articulating spacer achieved soft tissue compliance, allowed for ease of operation, reduced postoperative pain, improved function, and eradicated infection equal to standards reported in the literature. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series-no, or historical controls).