Matthias U. Schafroth

Less anterior knee pain with a mobile-bearing prosthesis compared with a fixed-bearing prosthesis.

AbstractAnterior knee pain is one of the major short-term complaints after TKA. Since the introduction of the mobile-bearing TKA, numerous studies have attempted to confirm the theoretical advantages of a mobile-bearing TKA over a fixed-bearing TKA but most show little or no actual benefits. The concept of self-alignment for the mobile bearing suggests the posterior-stabilized mobile-bearing TKA would provide a lower incidence of anterior knee pain compared with a fixed-bearing TKA. We therefore asked whether the posterior-stabilized mobile-bearing knee would in fact reduce anterior knee pain. We randomized 103 patients scheduled for cemented three-component TKA for osteoarthrosis in a prospective, double-blind clinical trial. With a 1-year followup, more patients experienced persistent anterior knee pain in the posterior-stabilized fixed-bearing group (10 of 53, 18.9%) than in the posterior-stabilized mobile-bearing group (two of 47, 4.3%). No differences were observed for range of motion, visual analog scale for pain, Oxford 12-item questionnaire, SF-36, or the American Knee Society score. The posterior-stabilized mobile-bearing knee therefore seems to provide a short-term advantage compared with the posterior-stabilized fixed-bearing knee. Level of Evidence: Level I, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Time-Action Analysis (TAA) of the Surgical Technique Implanting the Collum Femoris Preserving (CFP) Hip Arthroplasty. TAASTIC trial Identifying pitfalls during the learning curve of surgeons participating in a subsequent randomized controlled trial (An observational study)

BackgroundTwo types of methods are used to assess learning curves: outcome assessment and process assessment. Outcome measures are usually dichotomous rare events like complication rates and survival or require an extensive follow-up and are therefore often inadequate to monitor individual learning curves. Time-action analysis (TAA) is a tool to objectively determine the level of efficiency of individual steps of a surgical procedure.Methods/DesignWe are currently using TAA to determine the number of cases needed for surgeons to reach proficiency with a new innovative hip implant prior to initiating a multicentre RCT. By analysing the unedited video recordings of the first 20 procedures of each surgeon the number and duration of the actions needed for a surgeon to achieve his goal and the efficiency of these actions is measured. We constructed a taxonomy or list of actions which together describe the complete surgical procedure. In the taxonomy we categorised the procedure in 5 different Goal Oriented Phases (GOP):1. the incision phase2. the femoral phase3. the acetabulum phase4. the stem phase5. the closure paseEach GOP was subdivided in Goal Oriented Actions (GOA) and each GOA is subdivided in Separate Actions (SA) thereby defining all the necessary actions to complete the procedure. We grouped the SAs into GOAs since it would not be feasible to measure each SA. Using the video recordings, the duration of each GOA was recorded as well as the amount of delay. Delay consists of repetitions, waiting and additional actions. The nett GOA time is the total GOA time – delay and is a representation of the level of difficulty of each procedure. Efficiency is the percentage of nett GOA time during each procedure.DiscussionThis allows the construction of individual learning curves, assessment of the final skill level for each surgeon and comparison of different surgeons prior to participation in an RCT. We believe an objective and comparable assessment of skill level by process assessment can improve the value of a surgical RCT in situations where a learning curve is expected.

Learning curve analysis of the Collum Femoris Preserving total hip surgical technique

The aim of this study was to determine whether femoral neck preserving total hip arthroplasty would become less difficult and more efficient during the first 20 cases and to identify potential pitfalls during the introduction of this procedure. The difficulty and efficiency of the initial 20 procedures performed by four surgeons was prospectively determined by analysing a total of 68 video recordings using time-action analysis. This method measures the duration and efficiency of individual actions needed for a surgeon to achieve his or her goal. Afterwards, we reviewed all actions with a long duration and discussed possible causes of delay with the surgeons to identify possible pitfalls. We found a decrease of difficulty and an increase of efficiency during the first 20 cases and a more consistent execution after the initial five cases. Estimating the correct osteotomy level and stem curvature was often difficult, which resulted in a variable stem position. Radiologic analysis demonstrated a tendency for varus position and increased leg length throughout the series, even after the surgeons demonstrated technical proficiency.

Patient-related and work-related factors play an important role in return to work after total knee arthroplasty: a systematic review

Importance A growing group of patients with a total knee arthroplasty (TKA) are still working at the time of the surgery. The average time to return to work (RTW) is estimated at 3–6 months. There is a large range of time that patients need to RTW. Objective The objective of this review is to systematically identify beneficial and limiting factors that affect RTW after TKA. Evidence review PubMed and Embase were searched systematically to find studies that analysed prognostic factors for RTW in patients undergoing TKA. The following inclusion and exclusion criteria were used: patients with a TKA, studies that reported on RTW after TKA, patients had to be between 18 and 65 years and beneficial or limiting factors affecting RTW were described. Studies were included if written in English, German, French or Dutch. The Quality-in-Prognostic-Studies tool was used for the quality assessment of the included studies. Findings 11 of the 306 primarily identified studies met the inclusion criteria. 7 patient-specific and 11 work-related factors were beneficial for a faster RTW, like being male and having a high job qualification. There were three patient-specific and eight work-related factors that were limiting factors for the RTW, like being female and preoperative sick leave. Conclusions and relevance Patients that are male, have a high sense of urgency to return to work, have a high job qualification, are self-employed, with limited sick leave are those that are most likely for a successful and fast RTW. With the use of these factors, patients can be earlier identified as requiring better guidance preoperative and postoperatively for a more successful RTW. Level of evidence Level III.

Weer aan het werk na een totale knieprothese

SamenvattingDe knieprothese is een succesvolle operatie voor vermindering van pijn bij artrose van de knie. Voor weer kunnen werken, lijken de resultaten minder gunstig.