Is This the Research that Will Change Your Practice?

    These studies, presented at the AAOS Annual Meeting in Las Vegas, have the potential to redefine orthopaedic practice.

    By Susan Doan-Johnson

    At the start of the session on game-changing research presented at the American Academy of Orthopaedic Surgeons’ 2015 Annual Meeting, moderator Steven L. Frick, MD, made a bold prediction: “These are the papers that should change your practice when you go home tomorrow.”

    Is this just hyperbole, or is Dr. Frick on to something? Only time will tell.

    What’s clear is that the papers presented during this session are worthy of serious consideration: They were selected by the Annual Meeting’s subspecialty committees, whose members collectively reviewed thousands of abstracts submitted for presentation at the meeting – putting them in the perfect position to evaluate which papers truly reach game-changer status.

    In this summary we’ll focus only on the 8 papers pertinent to joint arthroplasty and sports medicine surgeons: 4 in total joint arthroplasty and 4 in sports medicine.

    Total Joint Arthroplasty

    Paper 007: 10 Year Results of Total Hip Arthroplasty with Highly Cross-linked Polyetheylene in Patients 50 years and Less
    Authors: Frank C. Bohnenkamp, MD; James A. Keeney, MD; Jeffrey B. Stambough, MD; John M. Martell, MD; Gail Pashos; John C. Clohisy, MD

    Recent experience has shown that metal-on-metal is not the optimal bearing surface for younger patients undergoing total hip arthroplasty (THA) – which begs the question, what is?

    In a retrospective analysis, the researchers compared clinical and radiographic results of THA in 2 groups:

    • 115 patients (122 hips) with a cobalt chrome (CoCr) and highly cross-linked polyethylene bearing (HXLPE) bearing surface
    • 97 patients with a CoCr on conventional polyethylene (CPE) bearing surface.

    In both groups, modified Harris hip and the UCLA scores were significantly higher following THA. There were more failures in the CPE group than in the HXLPE group (6.3% vs. 4.1%, respectively). The linear wear rate was lower in the HXLPE group than in the CPE group, and there was no radiographic evidence of osteolysis in the HXLPE group, compared with osteolysis in 17 hips in the CPE group.

    The authors concluded that a CoCr femoral head with an HXLPE liner appears to be an excellent choice for patients younger than age 50 who need a primary THA, with less polyethylene wear and osteolysis compared with a conventional acetabular liner.

    Paper 187, Aspirin as Prophylaxis Against Venous Thromboembolism Leads to Lower Incidence of Periprosthetic Joint Infection
    Authors: Ronald Huang, MD; Patrick S. Buckley, MD; Javad Parvizi, MD, FRCS; James J. Purtill, MD

    Surgeons at The Rothman Institute in Philadelphia have been successful in using aspirin for venous thromboembolism (VTE) prophylaxis instead of more aggressive anticoagulants such as warfarin. In doing so, they have discovered that their VTE protocol has also reduced the risk of periprosthetic joint infection in their total joint arthroplasty (TJA) patients.

    In this study of more than 18,000 consecutive primary TJA cases from January 2006 to December 2012, 13,344 patients received warfarin for 6 weeks following surgery and 4,728 patients received aspirin twice daily. Data analysis showed a PJI rate of 1.3% in patients receiving warfarin, compared with 0.4% in patients receiving aspirin for VTE prophylaxis.

    More aggressive anticoagulant therapy, they said, has been associated with a higher incidence of wound drainage, hematoma formation, and reoperation – all of which may increase the risk for infection following TJA. In their study, patients who received aspirin had fewer wound-related problems than those who received warfarin, which may explain the lower rate of PJIs in the aspirin group.

    Paper 331, Is Physician Quality Reported Outcomes Worth the Cost to Report to CMS?
    Authors: Stephen T. Duncan, MD; Kyle Leyshon, MS; Cale Jacobs, PhD; Christian P. Christensen, MD; William B. Macaulay, MD

    A proposal by the Centers for Medicare and Medicaid Services (CMS) would require surgeons to report patient outcomes of their total joint arthroplasty patients or face a penalty of 1.5% of their reimbursement in 2015 and 2% in 2016.

    Put in terms of real dollars, would the cost of collecting and reporting the data (database management, equipment, cost of extra clinic time to complete, and additional personnel) be worth that 1.5% to 2% in reimbursement? According to the authors of this study, it’s a resounding “no.”

    To come up with this answer, they used the current relative value unit (RVU) of 20.72 for reimbursement after total knee or total hip arthroplasty, and they assumed 125 total knee arthroplasties and 75 total hip arthroplasties at the current $35.6446/RVU. The surgeon would receive $147,711.22 in reimbursement for that number of procedures.

    The cost to report the patient-reported outcomes for this practice, the author calculated, would range from $26,316.16 to $78,193. Compare that with the penalty for failing to report these measures – $2,215.67 in 2015 and $2,954.22 in 2016 – and it seems this proposed CMS requirement would not be sustainable for most surgeons.

    Paper 408, Cementless Fixation has Better Outcomes in Younger Patients
    Authors: Stephen Graves, MD; David Davidson, MD; Richard De Steiger, MD; Peter L. Lewis, MB; Robyn Vial, MSc; Ann Tomkins; Elizabeth C. Griffith, BA; Michelle Lorimer; Yen-Liang Liu

    Data from joint replacement registries are important for comparing implants, identifying complications, and evaluating outcomes of techniques used in total joint arthroplasty. One of the issues, according to researchers from Australia, is that investigators who use registry data may not account for known confounding factors when drawing conclusions about the data.

    In their study, they looked at registry data reporting outcomes of fixation – cementless, cemented, and hybrid – in patients age 60 and younger who had undergone total hip arthroplasty for osteoarthritis between 1999 and 2012. Of the nearly 49,000 patients included, the breakdown of fixation was as follows: 35,906 cementless, 1,508 cemented, and 7,669 hybrid.

    To determine the optimum fixation in these patients, they excluded known prostheses-related confounding factors: metal-on-metal bearings, modular neck femoral components, and non-cross-linked polyethylene bearings. In doing so, they found that in this younger patient population, cementless fixation was the superior to the other types of fixation.

    In their abstract, the authors concluded, “When determining the difference in outcome related to fixation in younger patients, it is important to address the issue of prostheses-related confounders. When these are identified and excluded, cementless fixation has a significantly lower rate of revision after 2.5 years compared to both hybrid and cement fixation.”

    Sports Medicine

    Paper 529, Arthroscopic Distal Clavicle Resection with Concomitant Rotator Cuff Repair: Prospective Randomized Trial
    Authors: Jae-Chul Yoo, MD; Yong Bok Park, MD; Keun Min Park, MD; Dong Ho Kum, MD; Eunsu Lee, MD; Junho Kim; Young Hoo Ko, MD

    Tenderness from acromioclavicular joint (ACJ) pathology is rare; however, it often occurs with rotator cuff tears. In this study from South Korea, the authors compared the role of rotator cuff repair alone versus rotator cuff repair plus distal clavicle resection in resolving ACJ tenderness in patients with rotator cuff tears.

    The 55 patients (58 shoulders) in the study had full-thickness rotator cuff tears, ACJ tenderness, and radiologic signs of shoulder arthritis. Twenty-size shoulders were randomized to the rotator cuff repair plus distal clavicle resection group, and 32 shoulders were randomized to the rotator cuff repair only group; 21 and 26 shoulders, respectively, were included in the analysis due to insufficient follow-up or loss.

    With mean follow-up of 44.2 months for the distal clavicle resection plus rotator cuff repair group and 44 months for the rotator cuff repair alone group, the researchers found no differences in terms of postoperative American Shoulder and Elbow Surgeons score, Constant score, Visual Analog Scale score, patient satisfaction grade, and retear rate between two groups. Nor was there a difference in the number of patients who still had ACJ tenderness following surgery.

    Surgeons should carefully consider whether distal clavicle resection is needed in patients with rotator cuff tears, ACJ tenderness, and shoulder arthritis, as it appears rotator cuff repair alone is sufficient to provide relief of ACJ tenderness.

    Paper 530, Early Mobilization Following Mini-Open Rotator Cuff Repair: A Randomized Controlled Trial
    Authors: Robert A. Balyk, MD FRCSC; Martin J. Bouliane, MD; Fiona Styles-Tripp, PT, BScPT; Lauren A. Beaupre, PhD; Manoj K. Saraswat, MHS; Charlene R. Luciak-Corea, BScPT; Anelise Silveira, PT; Robert R. Glasgow, MD, FRCS; David M. Sheps, MD, MSc, FRCSC

    Patients who undergo a mini-open rotator cuff repair generally have the affected shoulder immobilized in a sling for 6 weeks to help with healing. But there are drawbacks, such as problems with range of motion and stiffness once the sling is removed.

    Is the sling necessary? To find out, Canadian researchers compared outcomes between rotator cuff patients who were immobilized after surgery and those who were allowed some mobilization of the shoulder during that 6-week period.

    Patients in the early mobilization group self-weaned from the sling as pain allowed and then performed active range-of-motion exercises for activities of daily living, while patients in the immobilized group stayed in the sling. That was only difference in care: During the 6-week study period, patients in both groups participated in self-assisted passive range-of-motion exercises, and after 6 weeks, they all had the same rehabilitation protocol.

    Patients were assessed at 6 weeks and 3, 6, 12, and 24 months after surgery. The authors found no differences in clinical outcomes between groups. Early mobilization did not minimize long-term pain and stiffness, but it also did not compromise shoulder power, health-related quality of life, or healing, leading the authors to conclude that patients can begin to actively use the affected shoulder in the 6 weeks after mini-open rotator cuff repair.

    Paper 706, Dynamic Intraligamentary Stabilization: A Doorway to Intrinsic Healing of the ACL
    Authors: Sufian Ahmad, MD; Stefan Schwienbacher; Sandro Kohl, MD

    Surgical reconstruction is typically the treatment of choice for a ruptured anterior cruciate ligament (ACL). Various repair techniques are being reconsidered, however, and a study from Switzerland examines one such technique: primary ACL repair plus dynamic intraligamentary stabilization (DIS).

    Fifty patients age 18 to 50 years underwent this procedure between March and December 2011. The authors collected data for Tegner, Lysholm, and International Knee Documentation Committee (IKDC) scores, as well as for Visual Analog Scale scores to assess patient satisfaction, at 3, 6, 12, and 24 months after surgery. They also evaluated objective measurement of anterior tibial translation at each follow-up visit.

    The authors found that in the first 6 months after surgery, anterior translation increased 1.8 ± 2.0 mm in relation to the healthy leg (p=0.008). Between the 3-month and 12-month follow-up visits, all scores improved significantly, and by the 12-month follow-up, patients had returned to their preinjury activity levels. Stability was not restored in 2 patients, and 3 patients suffered a re-rupture.

    The authors concluded that this procedure “could provide an effective option for treating acute ACL ruptures. Knee stability and function could be restored to normal levels while maintaining the ACL.”

    Paper 769, Clinical Validation of the “On-Track” vs. “Off-Track” Concept in Anterior Glenohumeral Instability
    Authors: Jay B. Cook, MD; James S. Shaha, MD; Douglas J. Rowles, MD; Craig R. Bottoni, MD; Steve Shaha, Prof; John M. Tokish, MD

    The interaction of bone loss on the glenoid and humeral sides (bipolar bone loss) determines if the lesions is “on-track” or “off-track,” and this is thought to be a reliable indicator of the risk for recurrent instability following arthroscopic stabilization surgery. No clinical research, however, had been done to test this theory – until now.

    This study included 57 patients age 20 to 42 years who underwent arthroscopic Bankart reconstruction, 10 of whom experienced recurrent instability following surgery. Patients with recurrent instability had worse SANE (Single Assessment Numeric Evaluation) and WOSI (Western Ontario Shoulder Instability Index) scores than those who did not experience recurrent instability.

    There were 49 shoulders in the on-track group, 4 of which failed (8.2%). The 8 shoulders in the off-track group fared much worse, with 6 failures (75%, p=0.0001). Six of the 10 patients (60%) with recurrent instability following surgery were off-track at the time of surgery. Among the 47 patients who were stable at latest follow up, only 2 (4.3%) were off-track (p=0.0001).

    The authors concluded that off-track lesions are significant predictors of recurrent instability after isolated Bankart reconstruction, correctly predicting failure in 75% of cases in this study.

    “Bipolar bone loss as measured by the track method is quite accurate in predicting success and failure after arthroscopic Bankart reconstruction in a clinical population,” they wrote in their abstract. “This method of assessment is encouraged as a routine part of the preoperative evaluation of all patients under consideration for arthroscopic anterior stabilization.”

    Author Information

    Susan Doan-Johnson is the Director of Editorial Content for ICJR.net.