Prospective randomised evaluation of a collagen/thrombin and autologous platelet haemostatic agent during cementless total hip arthroplasty.

BACKGROUND: Total hip arthroplasty (THA) can be associated with substantial peri-operative blood loss which can negatively influence a patient's clinical outcome. Few haemostatic agents have been tested in THA. The aim of this study was to determine whether the use of a collagen/thrombin/ autologous platelet haemostatic agent would result in a significant decrease of blood transfusions for patients undergoing primary THA. MATERIALS AND METHODS: THA patients meeting inclusion/exclusion criteria (n=109) were enrolled in this prospective, double-blind trial and randomised to a treatment arm (standard haemostatic methods plus haemostatic agent) or control arm (standard haemostatic methods only). The primary outcome was transfusion. Secondary outcome measures included peri-operative narcotic usage and post-operative haemoglobin levels, pain scores, function, and general health quality of life. RESULTS: Transfusions were required by 5/60 (8.3%) patients in the treatment group and 7/49 (14.3%) in the control group (p=0.33). The mean number of units transfused was not significantly different between the treatment group (2.2±1.3) and the control group (1.6±0.5) (p=0.36). Haemoglobin values on post-operative days 1, 2, and 3 were significantly higher in the treatment group (p=0.002, 0.04, and 0.02, respectively). Hip Disability and Osteoarthritis Outcome Score and Short Form-12 scores were not different between the two groups. DISCUSSION: In relatively healthy patients undergoing primary cementless THA there was no significant difference in number of transfusions or number of units transfused. It is unlikely that we will routinely use the investigated haemostatic agent to reduce blood loss in a healthy patient undergoing THA. The product may have some benefit in patients who refuse blood transfusions, have minimal ability to increase blood volume, are undergoing total joint revision, or have markedly low pre-operative haemoglobin levels, but this needs to be demonstrated.

The contribution of the acetabular labrum to hip joint stability: a quantitative analysis using a dynamic three-dimensional robot model.

The acetabular labrum provides mechanical stability to the hip joint in extreme positions where the femoral head is disposed to subluxation. We aimed to quantify the isolated labrum's stabilizing value. Five human cadaveric hips were mounted to a robotic manipulator, and subluxation potential tests were run with and without labrum. Three-dimensional (3D) kinematic data were quantified using the stability index (Colbrunn et al., 2013, "Impingement and Stability of Total Hip Arthroplasty Versus Femoral Head Resurfacing Using a Cadaveric Robotics Model," J. Orthop. Res., 31(7), pp. 1108-1115). Global and regional stability indices were significantly greater with labrum intact than after total labrectomy for both anterior and posterior provocative positions. In extreme positions, the labrum imparts significant overall mechanical resistance to hip subluxation. Regional stability contributions vary with joint orientation.

Evaluation of wound healing after direct anterior total hip arthroplasty with use of a novel retraction device.

Use of shorter incisions in minimally invasive surgery total hip arthroplasty (THA) may come at the cost of poorer cosmesis, possibly a result of the excessive retraction needed for visualization. This may be particularly relevant in the direct anterior approach, in which wound-healing issues are common. We prospectively investigated whether a specialized ring retractor was effective in minimizing wound-edge trauma, as evidenced by improved scar cosmesis. Fifty patients having direct anterior THA were randomized to surgery with or without ring retractor. Incisional photographs 2, 6, and 12 weeks after surgery were graded by 2 blinded plastic surgeons. Wound scores and patient satisfaction with scar appearance were similar between groups. Our results suggest no improvement in wound cosmesis with use of this retraction device.

Biomechanical analysis of posterior cruciate ligament reconstruction with aperture femoral fixation.

The goal of this study was to determine whether single-tunnel-double-bundle-equivalent posterior cruciate ligament (PCL) reconstruction using an aperture femoral fixation device better replicated normal knee kinematics than single-bundle reconstruction. Eight fresh-frozen human cadaver knees underwent arthroscopically assisted PCL reconstruction and were examined with a robotic testing system to assess knee joint kinematics under combinations of applied internal, neutral, and external rotational tibial torque and anteroposterior translational forces at 0°, 30°, 60°, 90°, and 120° flexion. Three conditions were tested: (1) intact PCL; (2) single-tunnel PCL reconstruction with anterolateral and posteromedial bundle fixation at 90°/90° (single bundle); and (3) 90°/0° (double-bundle equivalent), respectively. Posterior tibial translation was the primary outcome measure. Compared with the intact knee, double-bundle-equivalent reconstruction under external tibial torque allowed greater posterior translation across the flexion arc as a whole (P=.025) and at 30° flexion (P=.027) when results were stratified by flexion angle. No other kinematic differences were found with single-bundle or double-bundle-equivalent fixation, including mediolateral translation and both coupled and isolated tibial rotation (P>.05). Single-bundle PCL reconstruction closely approximated native knee rotational and translational kinematics, whereas double-bundle-equivalent reconstruction permitted increased posterior translation with applied external tibial torque, particularly at lower flexion angles. Single-bundle PCL reconstruction provides knee stability similar to the intact condition, making it a practical alternative to conventional double-bundle PCL reconstruction. The authors found that double-bundle-equivalent reconstruction provided no advantage to justify its clinical use.

Comprehensive approach to the evaluation of groin pain.

Groin pain is often related to hip pathology. As a result, groin pain is a clinical complaint encountered by orthopaedic surgeons. Approximately one in four persons will develop symptomatic hip arthritis before age 85 years. Groin injuries account for approximately 1 in 20 athletic injuries, and groin pain accounts for 1 in 10 patient visits to sports medicine centers. Many athletes with chronic groin pain have multiple coexisting pathologies spanning several disciplines. In treating these patients, the orthopaedic surgeon must consider both musculoskeletal groin disorders and nonorthopaedic conditions that can present as groin pain. A comprehensive history and physical examination can guide the evaluation of groin pain.

Surgical outcome following arthroscopic fixation of acromioclavicular joint disruption with the tightrope device.

The objective of this study was to evaluate the preliminary radiographic and clinical results of grade IV and V acromioclavicular joint disruption repair using the arthroscopic Arthrex acromioclavicular TightRope (Naples, Florida) fixation technique. Numerous procedures have been described for surgical management of acromioclavicular joint disruption. The TightRope device involves an arthroscopic technique that allows nonrigid anatomic fixation of the acromioclavicular joint. A cohort of 10 men and 2 women with a mean age of 43 years (range, 25-61 years) underwent the acromioclavicular joint TightRope procedure between April 2007 and October 2009. Eleven patients had either Rockwood grade IV or V disruptions and 1 sustained a distal third clavicle fracture with acromioclavicular joint disruption. Data was collected from a chart review. Patients were evaluated clinically, radiographically, by the simple shoulder test, and by overall satisfaction. There were 2 failures of reduction and 1 loss of reduction at final radiographic follow-up. The rate of fixation failure was 16.6%. All patients had >110° of total elevation. The majority of patients obtained satisfactory functional results according to the Simple Shoulder Test averaging 11 of 12 questions answered positively (range, 7-12; standard deviation, 1.50) and 11 of 12 patients were satisfied with the procedure. At final phone interview at approximately 2 years postoperatively, 6 patients were lost to follow-up. The remaining patients were all satisfied with the procedure and no patients reported subjective loss of reduction or deterioration of function. Simple Shoulder Test average was maintained with 11 of 12 positively answered questions (range, 7-12; standard deviation, 2.0) This case series revealed a high rate of fixation failure with the TightRope system. Still, most patients were satisfied with the procedure and achieved high functional shoulder results.

Matrix metalloproteinase expression in basal cell carcinoma: relationship between enzyme profile and collagen fragmentation pattern.

Matrix metalloproteinases (MMPs) with collagenolytic and gelatinolytic activities are up-regulated in basal cell carcinoma. In the present study we demonstrate that the major collagenolytic enzyme detected is MMP-1 (interstitial collagenase) while gelatinolytic enzymes include both MMP-2 (72-kDa gelatinase A) and MMP-9 (92-kDa gelatinase B). Significant fractions of all three enzymes are present as active forms. In spite of the fact that high levels of gelatinolytic enzymes are present, the major fragmentation products resulting from digestion of intact type I collagen are the 1/4 and 3/4 fragments (products of MMP-1-mediated digestion). Thus, it appears that the gelatinolytic enzymes are not capable of degrading the collagen fragments as rapidly as they are produced. Since previous studies have demonstrated that interaction of interstitial fibroblasts with high molecular weight fragments of type I collagen leads to increased MMP production, the present results suggest a mechanism underlying altered function of stromal elements in the connective tissue adjacent to the growing neoplasm.