Nicholas T. Ting

Use of Knotless Suture for Closure of Total Hip and Knee Arthroplasties: A Prospective, Randomized Clinical Trial

We performed a prospective, randomized clinical trial to evaluate the efficacy of using a bidirectional barbed suture compared with traditional sutures in the deep closure of primary total hip (25) and knee (35) arthroplasties. Complications, time to closure, and length of surgery were evaluated. Closure was noted to be significantly faster (9.3 vs 13.6 minutes, P < .005) in the barbed suture group. Wound-related complications were similar (3 cases) in both groups at 3-month follow-up. Although this study supports the use of barbed technology as a functionally comparable and more efficient modality of wound closure with the potential for costs savings based on reduced operative time, the cost-effectiveness of its adoption is institution dependent and will rely on the optimization of all other perioperative factors.

Acute Hematogenous Infection following Total Hip and Knee Arthroplasty

Forty consecutive patients (42 joints; 22 TKA, 20 THA) treated for acute hematogenous infections were reviewed. All patients underwent irrigation and debridement and exchange of the modular components. At a mean of 56 months (range, 25-124 months) recurrent infection, requiring surgery, developed in 9 of the 42 joints (21%); 8 of the 9 recurrent infections were in patients with a staphylococcal infection (P = 0.0004). Ten of the 40 patients (25%) died within 2 years of infection. Irrigation and debridement for the treatment of an acute hematogenous infection was successful in the majority of patients (76% survivorship at 2 years). Non-staphylococcal infections had a particularly low failure rate (96% survivorship at 2 years). The 2 year mortality rate among this subset of patients was strikingly high.

Treatment of early postoperative infections after THA: a decision analysis.

BackgroundThe treatment for an early postoperative periprosthetic infection after cementless THA that results in the highest quality of life after the control of infection is unknown. Although common treatments include irrigation and débridement with component retention, a one-stage exchange, or a two-stage exchange, it is unclear whether any of these provides a higher quality of life after the control of infection.Questions/purposesWe projected, through decision-analysis modeling, the possible estimated final health states defined as health-related quality of life based on quality-of-life studies of an early postoperative periprosthetic infection after cementless THA treated by irrigation and débridement, one-stage exchange, or two-stage exchange.MethodsPublications addressing early postoperative infections after THA were analyzed for the estimated rate of infection control and quality-of-life measures after a specific treatment. Decision analysis was used to model the different treatments and describe which, if any, treatment results in the greatest quality of life after early THA infection.ResultsIn the model, a one-stage exchange was the treatment for early THA infection that maximized quality-of-life outcomes if the probability of controlling the infection exceeded 66% with this procedure. If the probability of infection control of a one-stage exchange was less than 66% or that of irrigation and débridement was greater than 60%, then irrigation and débridement appeared to result in the greatest quality-of-life outcome.ConclusionsA decision analysis using estimates of infection control rate and quality-of-life outcomes after different treatments for an early postoperative infection after THA showed possible outcomes for each treatment.Level of Evidence Level II, economic and decision analyses. See Guidelines for Authors for a complete description of levels of evidence.

Revision Total Knee Arthroplasty for Stiffness

Few studies have evaluated the results of revision of well-fixed components for stiffness, and some authors have recommended against this intervention based on poor reported results. Thirty-five consecutive patients underwent revision of both femoral and tibial components for stiffness. At a mean of 54.5 months (range, 25-134), the mean arc of motion improved by 44.5 degrees from a preoperative mean of 53.6 degrees to a postoperative mean of 98.1 degrees (P < .0001). The arc of motion improved by more than 30 degrees in 75% (24/32) of patients evaluated at a minimum of 2 years. Seventeen (49%) of the 35 patients required a further intervention for stiffness or sustained a complication. These results suggest that revision total knee arthroplasty for stiffness can be performed with a reasonable expectation of improvement, although the risk of complications and additional operative procedures is substantial.

Use of a Barbed Suture in the Closure of Hip and Knee Arthroplasty Wounds

Wound closure in primary and revision total hip and knee arthroplasty is an essential and critical component of the procedure. A well-performed closure may take up to 20 to 30 minutes for primary and revision surgeries, respectively. Traditionally, a layered closure is performed using various forms of absorbable and nonabsorbable sutures placed in an interrupted fashion, requiring the surgeon to tie knots to secure each stitch. Disadvantages of knot tying include increased operative time, prominence in subcutaneous layers, and local tissue ischemia. Recently, a bi-directional, barbed suture has been introduced that affords surgeons the ability to close soft tissue layers in a running fashion without the need for knot tying. The bi-directional nature of the barbs allows for simultaneous closure from the wound center, therefore offsetting the increased cost per suture by the decreased number of sutures used and the time saved in the operating room to close the incision. Additional potential advantages of using knotless sutures include enhanced biomechanical strength, increased resistance to catastrophic arthrotomy failure, and a more watertight closure. Our early data support the efficiency and safety of using this suture in total joint arthroplasty wound closure. This article reviews our experience and describes the technique for using barbed sutures during wound closure in 940 cases of primary and revision total joint arthroplasties.

External Iliac Artery Injury Complicating Prosthetic Hip Resection for Infection

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 Kohlers 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.

Diagnosis of Periprosthetic Joint Infection—An Algorithm-Based Approach

BACKGROUND Periprosthetic joint infection (PJI) remains one of the most challenging and devastating modes of failure after total hip and knee arthroplasties. Despite the profound urgency and impact of PJI on an individual and societal basis, historically, there have not been standardized definitions of and diagnostic algorithms for infection after total joint arthroplasty. METHODS In a recent symposium, the American Academy of Hip and Knee Surgeons put forth a standardized approach to the prevention, diagnosis, and management of the patient with a suspected PJI. RESULTS This review article summarizes these findings, and reviews the algorithmic approach to the diagnosis of PJI. CONCLUSION The diagnosis of PJI is easily made in our experience in 90% of patients by getting an erythrocyte sedimentation rate and C-reactive protein followed by selective aspiration of the joint if these values are elevated or if the clinical suspicion is high. Synovial fluid obtained should be sent for a synovial fluid white blood cell count, differential, and cultures.

Dislocation After Total Hip Arthroplasty

Modularity in total hip arthroplasty (THA) allows surgeons to optimize implant reconstruction to patient anatomy intraoperatively. Dual-modular femoral neck stem or “dual-taper” THA implants possess interchangeable necks, providing additional modularity at the neck stem interface. Modular taper designs have the potential to allow precise reconstruction of center of rotation of the hip by facilitating adjustments in limb length, femoral neck version, and hip offset in order to optimize hip biomechanical parameters. Recently, there is increasing concern regarding this stem design as a result of the growing numbers of clinical failures due to fretting and corrosion at neck-stem taper junction, in a process that has been described as mechanically assisted crevice corrosion (MACC). Implant, surgical, and patient factors have been identified as likely contributing factors responsible for taper corrosion in dual-modular neck stem THA. There should be a low threshold to conduct a systematic clinical evaluation of patients with dual-modular neck stem THAs as early recognition and diagnosis will ensure prompt and appropriate treatment. As painful dual-modular neck stem total hip arthroplasties have various intrinsic and extrinsic causes, patients should be evaluated utilizing systematic risk stratification algorithms. Although specialized test such as metal ion analysis and cross -sectional imaging modalities such as MARS MRI and ultrasound should be used to optimize clinical decision- making, over-reliance on any single investigative tool in the clinical decision-making process should be avoided. Further research is required to gain understanding of implant, surgical, and patient risk factors associated with taper corrosion in dual- modular neck stem THA.

Revision Total Knee Arthroplasty: Management of Bone Loss

Bone loss is a common problem in revision total knee arthroplasty (TKA). The potential causes of bone loss are numerous, including osteolysis, septic loosening, direct mechanical bone loss, stress shielding, or iatrogenic from implant removal. Each revision TKA presents a unique challenge, depending on the magnitude of bony deficiency and the combination of etiologies. Preoperative and intraoperative evaluation of bone deficiency can predict the options for reconstruction. In the management of bone loss in revision TKA, it is imperative to consider not only the defect size and the extent of metaphyseal involvement but also patient demographics, including age, BMI, activity level, and life expectancy. The armamentarium of available treatment options is broad and includes polymethylmethacrylate (PMMA) with or without reinforcing screws; morselized or structural allograft; modular TKA systems including stems, wedges, and metal augments; and orthopedic salvage systems such as mega- or tumor prostheses. While morselized allograft is a suitable option for smaller, contained defects, use of allograft has inherent disadvantages, including risk of disease transmission, late resorption, and fracture/nonunion in the case of bulk allografts. The introduction of ultraporous metal augments and cones offers additional options to address structural defects in revision TKA, even in the face of metaphyseal compromise. Each revision is unique, and the degree of bone loss can be widely variable, making a strict treatment algorithm often impractical. Hence, proper treatment of bone loss entails understanding the multitude of management options in addition to the defect and patient being treated.