Omer F. Bilgen

Load Sharing and Ligament Strains in Balanced, Overstuffed and Understuffed UKA. A Validated Finite Element Analysis

The aim of this study was to quantify the effects of understuffing and overstuffing UKA on bone stresses, load distribution and ligament strains. For that purpose, a numerical knee model of a cadaveric knee was developed and was validated against experimental measurements on that same knee. Good agreement was found among the numerical and experimental results. This study showed that, even if a medial UKA is well-aligned with normal soft tissue tension and with correct thickness of the tibia component, it induces a stiffness modification in the joint that alters the load distribution between the medial and lateral compartments, the bone stress and the ligament strain potentially leading to an osteoarthritic progression.

Venous thromboembolism prophylaxis in major orthopaedic surgery: A multicenter, prospective, observational study

OBJECTIVES We investigated risk factors for venous thromboembolism (VTE), prophylaxis measures employed, and incidence of symptomatic deep venous thrombosis (DVT) and pulmonary embolism (PE) in patients undergoing major orthopaedic surgery (MOS). METHODS An open, multicenter, prospective, observational study was conducted in 21 medical centers, comprising 899 patients. Of these, 316 patients (35.2%) underwent total hip arthroplasty (THA), 328 patients (36.5%) underwent total knee arthroplasty (TKA), and 255 patients (28.4%) underwent surgery for hip fractures (HF). Pharmacologic prophylaxis was employed in all the patients. RESULTS Risk factors for VTE were seen in 73.2% of the patients, the most common being obesity (72%) and prolonged immobilization (36.3%). Low-molecular-weight heparin (91.1%) and fondaparinux (8.9%) were used for prophylaxis, which was short-term in 273 patients (30.4%) and long-term in 626 patients (69.6%). Mechanical prophylaxis was performed with compression stockings in 610 patients (67.9%) and by intermittent pneumatic compression in 67 patients (7.5%). During three-months of follow-up, symptomatic DVT and PE were seen in eight (0.9%) and four patients (0.4%), respectively. Mortality occurred in 10 patients (1.1%). Complications of major and minor bleeding were seen in eight (0.9%) and 40 (4.5%) patients, respectively. CONCLUSION Effective VTE prophylaxis is associated with low risk of clinically apparent DVT and PE in MOS.

The Effect of Alpha-2 Macroglobulin on the Healing of Ruptured Anterior Cruciate Ligament in Rabbits

To investigate the effect of modification of biological environmental conditions, one of the factors influencing the healing of anterior cruciate ligament rupture, we performed experimental anterior cruciate ligament ruptures on New Zealand rabbits. After experimental rupture, intra-articular alpha-2 macroglobulin was injected into the knees of the rabbits in the experiment group to prevent structural changes resulting from the enzymatic reactions in the ruptured anterior cruciate ligament. At the end of 10th day of the experiment, we observed that the anterior cruciate ligaments in the experiment group had retained their prerupture brightness and volume when compared with the control group in which intra-articular alpha-2 macroglobulin had not been injected. We also noted that the anterior cruciate ligaments in the experiment group had not retracted or swollen, the incision sites were regular and clean, and they did not show any signs of degeneration. In the histological examination, the anterior cruciate ligaments in the control groups showed disruption of the collagen network and a significant diminution in number of fibroblasts and fibrocytes (p <. 001). At the end of this study, we concluded that the necessary conditions for the healing and repair of ruptured anterior cruciate ligament could exist if the enzymatic and biological environments were under control.

Acetabular reconstruction by impacted cancellous allografts in cementless total hip arthroplasty revision

OBJECTIVE The aim of this study was to evaluate the primary and secondary stability, where 100% or virtually 100% of the uncemented acetabular component contacted with impacted cancellous allografts, focusing especially on the amount of graft used and rim contact. METHODS Fifteen cases of acetabular reconstruction using impacted cancellous allografts and cementless porous-coated component in which 100% or virtually 100% of the component contacted only with the allograft were reviewed. Mean follow-up was 97.5 (range: 58 to 130) months after revision. The Harris hip score was used to evaluate clinical results. Radiographic evaluations were done using standard anteroposterior views obtained at the final follow-up. RESULTS Two patients underwent re-revision. The mean Harris hip score of the remaining 13 patients was 88.3±11.9 (range: 68 to 100) at the final follow-up. Early postoperative radiographs showed mean angle of inclination of 45° (range: 30° to 55°). There was a mean migration of 6.2±7.8 (range: 0 to 29) mm and the migration amount did not differ according to rim contact (p=0.054). There was no correlation between migration and amount of graft used (p>0.05). There was a significant correlation between migration and follow-up time (p<0.01). CONCLUSION Our results imply that 50% host bone contact is not absolutely necessary to form a stable construct while restoring the centre of hip rotation.

Functional results of conservative therapy accompanied by interscalane brachial plexus block and patient-controlled analgesia in cases with frozen shoulder.

OBJECTIVES We evaluated the efficacy of simultaneous interscalene block and catheter analgesia applied as an aid to conservative treatment in improving shoulder functions in patients with frozen shoulder. METHODS Three patients (2 women, 1 man; mean age 47 years) with frozen shoulder underwent conservative treatment including manipulation under interscalene brachial plexus block and subsequent rehabilitation under catheter analgesia to improve shoulder range of motion and function. Following manipulation under interscalene block, the patients were hospitalized for 15 to 28 days (mean 21 days) for an exercise program performed by a physiotherapist and orthopedist at least twice a day under interscalene catheter analgesia. Thirty minutes before each rehabilitation session, patient-controlled analgesia was administered via a pain relief pump. Active and passive range of motion (ROM) were measured and the severity of pain was rated using a visual analog scale (VAS) prior to and following interscalene block, during the exercise program, and at the end of the treatment. Functional assessments were made before and after treatment using the University of California in Los Angeles (UCLA) Shoulder Scale. The exercise program under interscalene analgesia was performed until pain-free and sufficient active movements were obtained, with at least 80% improvement in active and passive motion, a VAS score of 0-2, and an UCLA score of >27. RESULTS Compared to pretreatment values, the ROM values showed remarkable increases at the end of the treatment. Active ROM reached at least 30 degrees external rotation, 40 degrees internal rotation, 150 degrees flexion, 45 degrees extension, and 100 degrees abduction in all cases. On presentation, the VAS scores of all cases were 10 for both active and passive movements, whereas they ranged from 0 to 2 on discharge. The mean UCLA score increased from 12.3 to 30.3 after treatment. Immediately after the interscalene block, two patients exhibited signs of Horners syndrome which resolved spontaneously within an hour without the need for treatment. No complications or catheter-related problems such as infection, break-off, or displacement developed throughout the treatment period. There was no requirement for additional analgesia. CONCLUSION In patients with frozen shoulder, interscalene block and continuous patient-controlled analgesia via an interscalene catheter provided sufficient analgesia and contributed to the recovery of shoulder functions through an effective and safe exercise program, with no side effects or complications. However, further studies are needed to assess the feasibility of home applications of interscalene patient-controlled analgesia to increase cost-effectiveness and patient satisfaction.

Ogilvie’s syndrome following bilateral knee arthroplasty: a case report

Ogilvies syndrome, also known as acute colonic pseudo-obstruction, is an uncommon but severe postoperative complication of total hip and knee arthroplasty. This syndrome should be borne in mind after arthroplasty surgery. We present a case of this serious postoperative complication and aim to identify the risk factors and alert surgeons to the possibility and appropriate management of Ogilvies syndrome.

The Effect of Dislocation Type (Crowe Types I–IV) on Pelvic Development in Developmental Dysplasia of the Hip: A Radiologic Study of Anatomy

Classification of hip pathology in developmental dysplasia of the hip (DDH) helps in appropriate placement of implants during total hip arthroplasty. We examined preoperative unilateral and bilateral pelvic radiographs of 57 patients (114 hips) undergoing total hip arthroplasty because of DDH. Both sides of the pelvis were visually separated into 3 areas for comparison. When area ratios of hips with Crowe types II, III, and IV DDH were compared with ratios for healthy hips, values in hips with DDH were significantly low for the iliac wings, significantly high for the acetabular regions, and significantly low for the ischial area. Using a line crossing the healthy hips teardrop and parallel to a line joining the distal sacroiliac joints is useful for calculating limb-length discrepancy.

An Assessment of the Chondroprotective Effects of Intra-Articular Application of Statin and Tetracycline on Early-Stage Experimental Osteoarthritis

Objectives. To compare the effects of intra-articular application of statin and tetracyclines on cartilage and synovial tissue on experimental osteoarthritis. Methods. Osteoarthritis was created in 30 rabbits of 3 groups. The control group received saline intra-articularly, statin group, atorvastatin and the tetracycline group, doxycycline once a week for 3 weeks. Chondral and synovial tissues were evaluated macroscopically and histopathologically. Results. Macroscopic evaluation determined mean values of control group 3.0, statin group 0.56, and tetracycline group 2.5. Histopathological evaluations determined mean values; femoral medial condyle cartilage tissue, control group, 14.60 ± 1.00, statin group 2.20 ± 1.30, tetracycline group 12.7 ± 5.39: tibia medial plateau, control group, 14.33 ± 8.68, statin group 2.89 ± 1.96, tetracycline group, 15.90 ± 7.03: synovial tissue, control group 12.22 ± 3.63, statin group 4.33 ± 2.69, tetracycline group 10.70 ± 2.62. Average values of synovial tissue cell layer thickness were control group 14.46 ± 2.35 μm, statin group 10.56 ± 1.01 μm, tetracycline group 12.80 ± 0.79 μm. All measurements showed statistically significant differences between statin and control groups (P < 0.05) but not between tetracycline and control groups (P > 0.05). Conclusions. Tetracycline has little effect due to chemical modification requirement, and the effect is dose dependent. Statins have chondroprotective effects, so may become a novel therapeutic agent in osteoarthritis management after chemical processing.

Total hip arthroplasty for acetabular fractures: “Early Application”

BACKGROUND The aim of this study was to evaluate the functional and clinical results of early total hip arthroplasty performed to treat acetabulum fracture. METHODS Evaluation of 17 patients who were diagnosed with acetabulum fracture and treated with early total hip arthroplasty between January 2008 and October 2013 was performed. In all, 14 patients were male, and 3 were female, with mean age of 52 years (range: 29-80 years). Time elapsed between trauma and operation was mean of 13 days (range: 2-21 days). Observation period was average of 48.2 months (range: 24-70 months). Mean Harris Hip Score was 89.6 (range: 70-100). RESULTS In 13 patients, score was good or excellent. Total of 7 of 10 patients had returned to their pre-trauma jobs. Mean length of time for return to work was determined to be 7.2 months (range: 1.5-24 months). Of the total, 9 (52.9%) patients were diagnosed with heterotopic ossification according to Brooker Classification. CONCLUSION After acetabulum fracture, early total hip arthroplasty with the correct indications and appropriate patient can result in functional, pain-free hip joint with the advantages of early mobilization, early return to work, and decrease in reoperation risk. Heterotopic ossification prophylaxis should be considered in the presence of 1 or more risk factors, such as a head injury, high-energy trauma, or associated musculoskeletal injuries.