Ran Thein

The effect of clopidogrel and aspirin on blood loss in hip fracture surgery

INTRODUCTION Anti-platelet drugs are commonly used for primary and secondary prevention of thrombo-embolic events and following invasive coronary interventions. Their effect on surgery-related blood loss and perioperative complications is unclear, and the management of trauma patients treated by anti-platelets is controversial. The anti-platelet effect is over in nearly 10 days. Notably, delay of surgical intervention for hip fracture repair for >48 h has been reported to increase perioperative complications and mortality. PATIENTS AND METHODS Intra-operative and perioperative blood loss, the amount of transfused blood and surgery-related complications of 44 patients on uninterrupted clopidogrel treatment were compared with 44 matched controls not on clopidogrel (either on aspirin alone or not on any anti-platelets). RESULTS The mean perioperative blood loss was 899±496 ml for patients not on clopidogrel, 1091±654 ml for patients on clopidogrel (p=0.005) and 1312±686 ml for those on combined clopidogrel and aspirin (p=0.0003 vs. all others). Increased blood loss was also associated with a shorter time to operation (p=0.0012) and prolonged surgical time (p=0.0002). There were no cases of mortality in the early postoperative period. CONCLUSIONS Patients receiving anti-platelet drugs can safely undergo hip fracture surgery without delay, regardless of greater perioperative blood loss and possible thrombo-embolic/postoperative bleeding events.

Biomechanical Assessment of the Anterolateral Ligament of the Knee: A Secondary Restraint in Simulated Tests of the Pivot Shift and of Anterior Stability.

BACKGROUND Injury to the lateral capsular tissues of the knee may accompany rupture of the anterior cruciate ligament (ACL). A distinct lateral structure, the anterolateral ligament, has been identified, and reconstruction strategies for this tissue in combination with ACL reconstruction have been proposed. However, the biomechanical function of the anterolateral ligament is not well understood. Thus, this study had two research questions: (1) What is the contribution of the anterolateral ligament to knee stability in the ACL-sectioned knee? (2) Does the anterolateral ligament bear increased load in the absence of the ACL? METHODS Twelve cadaveric knees from donors who were a mean (and standard deviation) of 43 ± 15 years old at the time of death were loaded using a robotic manipulator to simulate clinical tests of the pivot shift and anterior stability. Motions were recorded with the ACL intact, with the ACL sectioned, and with both the ACL and anterolateral ligament sectioned. In situ loads borne by the ACL and anterolateral ligament in the ACL-intact knee and borne by the anterolateral ligament in the ACL-sectioned knee were determined. RESULTS Sectioning the anterolateral ligament in the ACL-sectioned knee led to mean increases of 2 to 3 mm in anterior tibial translation in both anterior stability and simulated pivot-shift tests. In the ACL-intact knee, the load borne by the anterolateral ligament was a mean of ≤10.2 N in response to anterior loads and <17 N in response to the simulated pivot shift. In the ACL-sectioned knee, the load borne by the anterolateral ligament increased on average to <55% of the load normally borne by the ACL in the intact knee. However, in the ACL-sectioned knee, the anterolateral ligament engaged only after the tibia translated beyond the physiologic limits of motion of the ACL-intact knee. CONCLUSIONS The anterolateral ligament is a secondary stabilizer compared with the ACL for the simulated Lachman, anterior drawer, and pivot shift examinations. CLINICAL RELEVANCE Since the anterolateral ligament engages only during pathologic ranges of tibial translation, there is a limited need for anatomical reconstruction of the anterolateral ligament in a well-functioning ACL-reconstructed knee.

The results of corrective osteotomy for valgus arthritic knees

PurposeTo evaluate the results of corrective varus osteotomy in the treatment of arthritic knees with valgus deformity.MethodsThe data were retrieved from a literature review. Each relevant study was screened for demographic details, surgical techniques, follow-up periods, clinical outcomes, and complications.ResultsA total of 27 publications describing the results of varus osteotomies for valgus arthritic knees were reviewed. All were small case series studies, variable in their patient population, surgical techniques, rehabilitation protocols, follow-up periods, clinical assessments and were categorized as level IV of scientific evidence.ConclusionThe role of varus osteotomy remains poorly defined. The literature generally supports this procedure in active and cooperative patients to reduce pain and delay the need for knee replacement. New techniques hold promising results regarding shortening of rehabilitation time and low reoperation and complication rates.Level of evidenceIV.

Osteosynthesis of unstable intracapsular femoral neck fracture by dynamic locking plate or screw fixation: early results.

Objectives: The purpose of this study was to compare the postoperative radiologic and clinical outcomes of telescopic femur neck screws and small locking plate device (Targon FN) (group 1) with multiple cancellous screws (group 2) for displaced intracapsular femoral neck fractures. Design: Comparison of a prospective collected data to a historical control group (retrospective). Setting: One community teaching hospital. Patients: Seventy-eight patients (group 1, 31; group 2, 47) underwent reduction and internal fixation of displaced intracapsular femoral neck fractures with either Targon FN device or multiple cancellous screws from March 2000 to July 2010. Their mean age was 53.7 years (SD: 16.4), and the mean follow-up period was 28.6 months. Main Outcome Measures: Treatment failure was considered to be either a nonunion, osteonecrosis, or revision surgery of any type. Treatment was regarded as successful in patients who did not show failure and had at least 1-year follow-up. Results: One patient in group 1 (3.2%) and 22 (46.8%) in group 2 had a nonunion (P = 0.0001). Four (12.9%) group 1 patients and 16 (34.0%) group 2 patients underwent revision surgery (P = 0.036). Four (12.9%) patients in group 1 and 4 (8.5%) group 2 patients had osteonecrosis of the femoral head (P = 0.531). Multivariate logistic regression showed that internal fixation by the fixed-angle fixation device decreased the odds ratio for overall complication by a factor of 0.23, for example, by 77% (P = 0.018). Conclusions: Performing internal fixation by a fixed-angle fixation device decreased nonunion rates and revision rates. It did not affect the rate of osteonecrosis. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Flexible pes planus in adolescents: body mass index, body height, and gender--an epidemiological study.

Background: Most studies on the prevalence of flexible pes planus (FPP) have been conducted in pediatric populations and older adults. There is limited comparable information on these parameters for the adolescent age group. The purpose of this study was to report the prevalence of FPP and its association with body mass index (BMI), body height, and gender among healthy and fit adolescents. Methods: The data for this study were derived from a medical database containing records of 17-year-old males and females before their recruitment into mandatory military service. Information on the disability codes associated with FPP according to the Regulations of Medical Fitness Determination was retrieved. Logistic regression models were used to assess the association between BMI, body height, and gender to various grades of FPP severity. Results: The study cohort included 825 964 adolescents (467 412 males and 358 552 females). The prevalence was 12.4% for mild FPP and 3.8% for severe FPP among the males and 9.3% and 2.4%, respectively, for the females. An increased BMI was associated with FPP in both males (overweight: odds ratio [OR] 1.385, confidence interval [CI] 1.352-1.419, P < .001; obese: OR 1.765, CI 1.718-1.813, P < .001) and females (overweight: OR 1.408, CI 1.365-1.620, P < .001; obese: OR 1.549, CI 1.481-1.620, P < .001). Body height was associated with a decreased risk of FPP when the highest height quintile was compared with the lowest height quintile in both males (OR 0.782, CI 0.762-0.802, P < .001) and females (OR 0.730, CI 0.707-0.754, P < .001) for all FPP severity grades. Conclusions: There was a greater prevalence of FPP among males compared with females in a general healthy adolescent age group. FPP was associated with increased BMI and shorter body height for all grades of FPP severity. Level of Evidence: Level II, diagnostic study.

Labor-Related Sacral Stress Fracture Presenting as Lower Limb Radicular Pain

In contrast to radicular pain during pregnancy, the incidence of postpartum radicular pain is rare. Sacral stress fractures are unusual but important causes for low-back and buttock pain and even postpartum radicular pain. To date, only 10 postpartum sacral stress fractures have been reported in the literature, with two descriptions of radicular pain as the presenting symptom. A 36-year-old woman, 7 days after her second delivery, presented with symptoms of spontaneous acute claudicating in conjunction with a left-leg radicular pain for 5 days. Imaging studies revealed a left sacral stress fracture. Bone mineral density was normal. The patient reported no pelvic, back, or radicular pain during the pregnancy, and had no history of menstrual irregularities, previous fracture, eating disorder, trauma or endocrine or metabolic diseases. No smoking or use of anticoagulation drugs was reported. Her obstetric and labor history showed no other risk factors. Epidural analgesia was used. Treatment consisted of toe-touch walking with crutches for 2 months, followed by full weight bearing, which resolved nearly all her symptoms. Clinicians should consider sacral fracture as a diagnostic possibility in postpartum and pregnant patients with lower back and/or buttock pain with or without radicular pain. Bone scintigraphy and computed tomography are considered harmful for the fetus. Magnetic resonance imaging, which is more suitable for pregnancy, is more sensitive than bone scintigraphy in revealing stress injuries of the bone. Physical examination and proper radiologic evaluation are the main keys for revealing the pathology.

Mid-term Outcome of Opening-wedge High Tibial Osteotomy for Varus Arthritic Knees

Gonarthrosis in the relatively young and active population causes major daily discomfort and disability. If the arthritic process is mainly limited to the medial compartment, the axis of a varus knee can be realigned laterally with high tibial osteotomy to unload the medial compartment and allow some cartilage regeneration and pain relief. This study describes the outcomes of patients who underwent opening-wedge high tibial osteotomies using Puddu plate (Arthrex, Naples, Florida) fixation. Eighteen patients (22 knees) with genu varum and medial compartment osteoarthritis were followed-up for an average of 6.3±2.3 years after high tibial osteotomy with Puddu plate fixation and iliac crest allograft. Clinical outcome was assessed by the Oxford Knee Score and subjective satisfaction rating. Pre- and postoperative radiographs were evaluated for tibiofemoral angle, Insall-Salvati index, and Kellgren-Lawrence Grading Scale for osteoarthritis. Mean patient age at surgery was 44±13.7 years, and mean body mass index was 29.1±4.7 kg/m(2). At last follow-up, mean Oxford Knee Score improved from 22.4±13.5 to 37.2±13.7 (P=.002). Average subjective satisfaction rate at last follow-up was 8±3. The measured tibiofemoral angle was corrected to an average genu valgum of 3.3°±4.8° (P=.001). No patient showed severe postoperative osteoarthritis (ie, Kellgren-Lawrence grade 4) at last follow-up. All radiographs showed full incorporation of the bone grafts. At the end of the study, 2 patients underwent total knee replacement. Opening-wedge high tibial valgus osteotomy with Puddu plate fixation can be a reliable procedure for the treatment of medial-compartment osteoarthritis of the knee associated with varus deformity.

Uncemented Arthroplasty for Metastatic Disease of the Hip Preliminary Clinical Experience

Improved longevity among patients with metastatic bone disease led to increasing incidence of pathologic and impending fractures around the hip. Cemented hip arthroplasty is considered to be the standard of care for this condition. The purpose of this study is to evaluate the outcome of uncemented hip arthroplasty in those patients. We performed a retrospective review of clinical and radiologic data of 57 consecutive patients (60 hips) who underwent an uncemented hip arthroplasty due to metastatic hip disease. Mean follow-up was 18.6 months (range, 5-60 months); overall 1-year survival and mortality rates were 58.5% and 38.3%, respectively. Multiple myeloma and metastatic prostate carcinoma patients had better outcome over other metastasis origin. At last follow-up, no prosthesis failure or operation-related major complication has been recorded.

Medial Subluxation of the Tibia After Anterior Cruciate Ligament Rupture as Revealed by Standing Radiographs and Comparison With a Cadaveric Model

Background: Biomechanical studies indicate that the tibia shifts medially and has a more valgus orientation in the anterior cruciate ligament (ACL)–deficient knee. However, it is not known whether these differences can be detected on standing radiographs. Purpose: To determine whether medial subluxation and more changes in coronal alignment of the tibia are detectable in both weightbearing radiographs and a cadaveric model simulating quiet standing. Study Design: Case series; Level of evidence, 4, and Descriptive laboratory study. Methods: Radiographic data were available for a cross-section of 74 patients with unilateral ACL tears. Tibial subluxation and coronal limb alignment were measured on hip-to-ankle weightbearing radiographs. Eight cadaveric knees were mounted on a 6 degree of freedom robot. Mediolateral position and varus-valgus alignment of the tibia relative to the femur were measured in response to 300-N axial compression simulating quiet standing at 5° and 15° of flexion with the ACL intact and sectioned. Results: Across all 74 patients included in the clinical study, the ACL-injured knee experienced 1.6 ± 2.3 mm (mean ± SD) of medial tibial subluxation compared with the contralateral uninjured knee (P < .001). The 24 patients with isolated ACL rupture exhibited 2.0 ± 1.8 mm of medial subluxation (P < .001). The mean coronal alignment of all 74 patients in the study was 0.7° ± 2.8° varus in the injured limb and 1.3° ± 2.6° varus in the uninjured contralateral limb (P = .0187). In the cadaveric model, the tibia translated 0.4 ± 0.5 mm more medially after sectioning of the ACL at 15° of flexion (P = .0485); however, no changes in coronal alignment were detected. Conclusion: The tibia shifts medially and is less varus in the ACL-deficient knee on standing radiographs. The medial tibial shift is reproduced in an axially loaded cadaveric model. Clinical Relevance: Medial tibiofemoral subluxation seen on frontal plane standing radiograph is an underappreciated sequela of isolated ACL rupture. The ability of ACL reconstruction to restore this aspect of ACL injury is not well understood and should be investigated further. Cadaveric models may be used to directly measure the mechanical effect of subtle changes in mediolateral position on articular contact stress as an indicator of the importance of this finding.

Lateral robotic unicompartmental knee arthroplasty.

Robotic-assisted unicompartmental knee arthroplasty (UKA) is accurate and repeatable. Lateral UKA is still considered a challenge, as the lateral side of the knee has different anatomy and kinematics compared with the medial side. The lateral compartment of the knee is less constrained than the medial compartment and is therefore less tolerant for mobile-bearing implants and ACL deficiency. However, the long-term outcomes of lateral UKA are scarce. Moreover, the impact of patellofemoral joint degeneration on the outcome of lateral UKA is unknown. We report our preliminary results with fixed bearing robotic-assisted lateral UKA, which are encouraging in the short term.