Addressing posterior tilt displacement during surgery to lower failure risk of sub-capital Garden types 1 and 2 femoral fractures.

INTRODUCTION: Sub-capital femoral fractures (SCFF) are impacted or non-displaced in Garden types 1 and 2, respectively. Non-surgical treatment is protected weight-bearing combined with physiotherapy and radiographic follow-up in selected patients. Traditionally, in situ pinning is the surgical treatment of choice. The aim of this study was to estimate whether the valgus deformity in Garden types 1 and 2 (AO classification 31B1.1 and 31B1.2) SCFF is a virtual perception of a posterior tilt deformity and if addressing this deformity improves patients' outcomes. MATERIALS AND METHODS: The records of 96 patients with Garden Types 1 and 2 SCFF treated in tertiary medical center between 1/2014 and 9/2017 were retrospectively reviewed. They all had preoperative hip joint anteroposterior and lateral radiographic views. 75 patients had additional computed tomography (CT) scans. Femoral head displacement was measured on an anteroposterior and axial radiograph projections and were performed before and after surgery. Preoperative 3D reconstructions were performed for a better fracture characterization, and assessment of the imaging was performed by the first author. RESULTS: The average age of the study cohort was 73 years (range 28-96, 68% females). There were 58 right-sided and 38 left-sided fractures. Ninety patients had Type 1 and six patients had Type 2 fractures. The average preoperative posterior tilt was 15 degrees and the average valgus displacement was 10 degrees on plain radiographs compared to 28 degrees and 11 degrees, respectively, on CT scans. Posterior tilt was found with a virtual perception as valgus-impacted fractures. The postoperative posterior tilt was corrected to an average of 3 degrees and the valgus displacement to 5 degrees. CONCLUSION: CT provides an accurate modality for measuring femoral head displacement and fracture extent. The posterior tilt displacement should be addressed during surgery to lower failure risk and the need for additional procedures. IRB APPROVAL: TLV-0292-15. LEVEL OF EVIDENCE: IV.

A Biomechanical Foot-Worn Device Improves Total Knee Arthroplasty Outcomes.

BACKGROUND: Biomechanics after total knee arthroplasty (TKA) often remain abnormal and may lead to prolonged postoperative recovery. The purpose of this study is to assess a biomechanical therapy after TKA. METHODS: This is a randomized controlled trial of 50 patients after unilateral TKA. One group underwent a biomechanical therapy in which participants followed a walking protocol while wearing a foot-worn biomechanical device that modifies knee biomechanics and the control group followed a similar walking protocol while wearing a foot-worn sham device. All patients had standard physical therapy postoperatively as well. Patients were evaluated throughout the first postoperative year with clinical measures and gait analysis. RESULTS: Improved outcomes were seen in the biomechanical therapy group compared to the control group in pain scores (88% vs 38%, P = .011), function (86% vs 21%, P = .001), knee scores (83% vs 38%, P = .001), and walking distance (109% vs 47%, P = .001) at 1 year. The therapy group showed healthier biomechanical gait patterns in both the sagittal and coronal planes at 1 year. CONCLUSION: A postoperative biomechanical therapy improves outcomes following TKA and should be considered as an additional therapy postoperatively.

[SURGICAL RESIDENCY IN THE ERA OF RESTRICTED WORKING HOURS].

INTRODUCTION: Post-Graduate Medical Education in the surgical professions, as in other medical professions as well, has gone through an organizational revolution during the past 10-15 years. Catalyzers of this change were the information revolution, technological changes, life-work balance needs of residents, legalization of the medical system and different duty hours' restrictions that followed. These changes require rethinking traditional Post-Graduate Medical Education and adaptation of teaching methods, quality measurement methods, new definition of program director's role and more. In this article we review these changes as they appear in updated literature and the significance of the changes in the Israeli health system since the last physicians' bargaining agreement of 2011.

Rivaroxaban significantly inhibits the stimulatory effects of bone-modulating hormones: In vitro study of primary female osteoblasts.

BACKGROUND: Anticoagulant therapy is a mainstay of treatment subsequent to major orthopedic surgeries. Evidence linking anticoagulant therapy, osteoporosis, and delayed fracture healing is not conclusive. We have previously reported that rivaroxaban significantly inhibited cell growth and energy metabolism in a human osteoblastic cell line. This study analyzed the response of primary female osteoblast cells to rivaroxaban in combination with various bone-modulating hormones. METHODS: Bone samples were taken from both premenopausal (pre-Ob) and postmenopausal (post-Ob) women. Cells were isolated from each sample and cultured to sub-confluence. Each sample was then treated with Rivaroxaban (10 µg/ml) in combination with the following hormones or with the hormones alone for 24 hours: 30nM estradiol-17ß (E2), 390nM estrogen receptor α (ERα) agonist PPT, 420nM estrogen receptor ß (ERß) agonist DPN, 50nM parathyroid hormone (PTH), and 1nM of vitamin D analog JKF. RESULTS: No effects were observed after exposure to rivaroxaban alone. When pre-Ob and post-Ob cells were exposed to the bone-modulating hormones as a control experiment, DNA synthesis and creatine kinase (CK)-specific activity was significantly stimulated with a greater response in the pre-Ob cells. When the cells were exposed to rivaroxaban in combination with bone-modulating hormones, the increased DNA synthesis and CK-specific activity previously observed were completely attenuated. CONCLUSIONS: Rivaroxaban significantly inhibited the stimulatory effects of bone-modulating hormones in both pre-Ob and post-Ob primary human cell lines. This finding may have clinical relevance for patients at high risk of osteoporosis managed with rivaroxaban or other factor Xa inhibitors.

Ochrobactrum anthropi-Caused Osteomyelitis in the Foot Mimicking a Bone Tumor: Case Report and Review of the Literature.

Osteomyelitis due to Ochrobactrum anthropi, a new genus Ochrobacterum widely distributed in the environment and occasionally associated with human infection, has been described in only a few case reports. We present a report of an unusual case of osteomyelitis caused by O. anthropi that was identified 9 years after a nail puncture to the lateral cuneiform bone. The patient was an 18-year-old male with a painful foot lesion that had originally been misdiagnosed as an osteolytic tumor. He underwent surgery and 2 firm pieces of rubber measuring 7 and 10 mm were removed from the lower portion of the lateral cuneiform bone, which appeared to be affected by an infection. After surgical debridement, O. anthropi was isolated from the bone cultures. The patient was successfully treated with a 6-week course of oral ciprofloxacin and clindamycin. At 1 year after the corrected diagnosis and appropriate treatment, he was symptom free and had resumed regular activities and an athletic lifestyle.

Long-Term Outcomes Following Reduction and Fixation of Displaced Subcapital Hip Fractures in the Young Elderly.

BACKGROUND: The surgical treatment of hip fractures remains controversial especially when considering age. OBJECTIVES: To investigate the long-term functional outcomes of displaced subcapital hip fractures that were reduced and surgically fixed using parallel cannulated screws in patients aged 60 years and younger. METHODS: During the period 1996-2005, 27 patients under age 60 with displaced subcapital hip fractures classified as Garden III or IV were treated with fracture reduction and surgical internal fixation using cannulated screws. Patient outcomes were assessed using the Harris Hip Score (HHS) and physical examination. RESULTS: During a follow-up period of 8-17 years 4 of the 27 patients (14.8%) developed non-union/femoral head avascular necrosis and had undergone hip arthroplasty. All reoperations were performed within the first year after fracture fixation, all in the 50-60 year old age group. The revision rate among patients 50-60 years old was significantly higher than that of patients 50 years and younger (40% vs. 0%, P = 0.037). Mean HHS was higher for patients not requiring revision surgery (85.4) than for patients with revision surgery (75.5), but this difference was not significant. CONCLUSIONS: Internal fixation using fracture reduction and cannulated screw fixation is a successful treatment modality for displaced subcapital hip fractures in patients under 50 years old. Patients aged 50-60 may have a higher risk of avascular necrosis or non-union and require arthroplasty, often within the first year after fracture fixation. The long-term outcome following these fractures is good when excluding patients who had early complications.

Platelet-rich plasma did not improve early healing of medial collateral ligament in rats.

BACKGROUND: The medial collateral ligament (MCL) is the most frequently injured ligament of the knee. Platelet-rich plasma (PRP) is a relatively new treatment option developed to enhance the healing response after injury to different tissue types. This study aimed at investigating whether the addition of PRP to MCL tears in rats would alter healing both biomechanically and histologically. METHODS: Bilateral full-thickness tears of the MCL were surgically induced in the knees of 32 rats. Right ligament was saturated with PRP (n = 32, study group), and the left ligament was saturated with saline (n = 32, control group). The animals were killed 3 weeks later and the surgical sites were evaluated by gross inspection, biomechanically and histologically. RESULTS: There was no gross difference in the mass of granulation tissue, load to failure, stiffness and displacement between the study and control groups. Histological examination by means of maturity score revealed no significant differences between the study and control groups. CONCLUSION: The addition of PRP to a healing MCL did not improve any of the outcome measures in this model.

Mortality and reoperations following lower limb amputations.

BACKGROUND: Above-the-knee amputations (AKA) and below-the-knee amputations (BKA) are commonly indicated in patients with ischemia, extensive tissue loss, or infection. AKA were previously reported to have better wound-healing rates but poorer rehabilitation rates than BKA. OBJECTIVES: To compare the outcomes of AKA and BKA and to identify risk factors for poor outcome following leg amputation. METHODS: This retrospective cohort study comprised 188 consecutive patients (mean age 72 years, range 25-103, 71 males) who underwent 198 amputations (91 AKA, 107 BK 10 bilateral procedures) between February 2007 and May 2010. Included were male and female adults who underwent amputations for ischemic, infected or gangrenotic foot. Excluded were patients whose surgery was performed for other indications (trauma, tumors). Mortality and reoperations (wound debridement or need for conversion to a higher levelof amputation) were evaluated as outcomes. Patient- and surgery-related risk factors were studied in relation to these primary outcomes. RESULTS: The risk factors for mortality were dementia [hazard ratio (HR) 2.769], non-ambulatory status preoperatively (HR 2.281), heart failure (HR 2.013) and renal failure (HR 1.87). Resistant bacterial infection (HR 3.083) emerged as a risk factor for reoperation. Neither AKA nor BKA was found to be an independent predictor of mortality or reoperation. CONCLUSIONS: Both AKA and BKA are associated with very high mortality rates. Mortality is most probably related to serious comorbidities (renal and heart disease) and to reduced functional status and dementia. Resistant bacterial infections are associated with high rates of reoperation. The risk factors identified can aid surgeons and patients to better anticipate and possibly prevent severe complications.

Opiates do not violate the viability and proliferative activity of human articular chondrocytes.

Articular cartilage injuries present a challenge for the clinician. Autologous chondrocyte implantation embedded in scaffolds are used to treat cartilage defects with favorable outcomes. Autologous serum is often used as a medium for chondrocyte cell culture during the proliferation phase of the process of such products. A previous report showed that opiate analgesics (fentanyl, alfentanil and diamorphine) in the sera have a significant inhibitory effect on chondrocyte proliferation. In order to determine if opiates in serum inhibit chondrocyte proliferation, twenty two patients who underwent knee arthroscopy and were anesthetized with either fentanyl or remifentanil were studied. Blood was drawn before and during opiate administration and up to 2 h after its discontinuation. The sera were used as medium for in vitro proliferation of both cryopreserved and freshly isolated chondrocytes, and the number and viability of cells were measured. There was no difference in the yield or cell viability between the serum samples of patients anesthetized with fentanyl when either fresh or cryopreserved human articular chondrocytes (hACs) were used. Some non-significant reduction in the yield of cells was observed in the serum samples of patients anesthetized with remifentanil when fresh hAC were used. We conclude that Fentanyl in human autologous serum does not inhibit in vitro hAC proliferation. Remifentanil may show minimal inhibitory effect on in vitro fresh hAC proliferation.

The anterior inferior iliac spine: size, position, and location. An anthropometric and sex survey.

PURPOSE: The purpose of this study was to investigate and describe the size, location, and position of the anterior inferior iliac spine (AIIS) in normal individuals. METHODS: We reviewed 50 computed tomography (CT) scans of 50 patients without hip pain or pathologic features. Mean patient height was 169.8 cm (women, 163 cm; men, 176.8 cm) and mean weight was 69.6 kg (women, 63.8 kg; men, 75.4 kg). We used all scans to measure both the left and right AIIS for the anatomic description of 100 AIISs. We measured AIIS dimensions, specifically length, width, and height. We also measured vertical, horizontal, and straight distances between the most anteroinferior prominence of the AIIS and the acetabular rim. We normalized AIIS size and distances from the acetabular rim according to the patient's height and body mass index (BMI). We also assessed the version of the AIIS using 2 angles. The first angle was the angle between the AIIS midaxis line and a plumb line, and the second angle was calculated as the angle subtended by the AIIS midaxis line and the ilium midaxis line. RESULTS: There were no significant differences between the AIIS in men and women in all measurements (except the width of the AIIS) when normalized to the patient's height and BMI. There were no significant differences in AIIS dimensions when comparing side-to-side differences in the entire study population. CONCLUSIONS: In quantifying AIIS dimensional size, distance from the anterior acetabular rim, and version, this study found no significant difference in all measurements normalized to patient size (height and BMI) between the left and right sides, and no significant sex difference was found in AIIS measurements, except the width of the AIIS. CLINICAL RELEVANCE: Morphologic variations that deviate from these normal values may help the clinician identify cases of subspinal impingement.

Clinical and radiographic outcomes of 139 hips with articular surface replacement total hip arthroplasty*.

BACKGROUND: The articular surface replacement (ASR) total hip arthroplasty (THA) was recently recalled from the market due to high failure rates. This modality was used frequently by surgeons at our medical center. OBJECTIVES: To assess the clinical and radiographic outcomes in patients following the surgery and determine the revision rate in our cohort. METHODS: Between 2007 and 2010 139 hips were operated on and evaluated in our clinic. All patients underwent a clinical interview, function and pain evaluation, as well as physical examination and radiographic evaluation. When necessary, patients were sent for further tests, such as measuring cobalt-chromium levels and magnetic resonance hip imaging. RESULTS: With an average follow-up of 42 months the revision rate was 2% (3/139). Patients reported alleviation of pain (from 8.8 to 1.7 on the Visual Analog Scale, P < 0.001), good functional outcomes on the Harris Hip Score, and improved quality of life. Overall satisfaction was 7.86 on the reversed VAS. For patients who required further tests, clinical and radiographic outcomes were significantly poorer than for the rest of the cohort. Average blood ion levels were high above the normal (cobalt 31.39 ppb, chromium 13.32 ppb), and the rate of inflammatory collection compatible with pseudotumors on MRI was 57%. DISCUSSION: While our study favors the use of the ASR implant both clinically and radiographically, some patients with abnormal ion levels and inflammatory collections on MRI might require revision in the future.

Surgical approach and prosthesis fixation in hip arthroplasty world wide.

BACKGROUND: Hip arthroplasty is one of the most common and successful surgical procedures worldwide. Component design and materials as well as surgical techniques constantly evolve. There is no consensus among surgeons regarding the ideal surgical approach and method of fixation. MATERIALS AND METHODS: 292 orthopedic surgeons of 10 subspecialties from 57 countries were surveyed on their choice of surgical approach and prosthesis fixation in hip arthroplasty. Their preferences were analyzed according to country of origin, field of expertise and seniority, and compared to current publications. RESULTS: The response rate was 95-98 %. Surgeons were split between the posterior approach (45 %) and the direct lateral approach (42 %) followed by the anterior approach (10 %) or other (3 %). North American surgeons favored the posterior approach more often than Europeans (69 % compared to 36 %, P < 0.0001) and surgeons from other countries (69 % compared to 45 %, P = 0.01). Sixty-eight percent of all surgeons routinely used noncemented hip prosthesis while 16 % use cemented and 16 % hybrid fixation. Noncemented fixation was preferred among surgeons from Europe and North America compared to other countries (73 % compared to 55 %, P < 0.05). There were no significant differences based on subspecialty, seniority or the number of years of experience. CONCLUSIONS: The most common surgical approaches in use in hip arthroplasty are posterior and lateral. Anterior approach is used by a minority of orthopedic surgeons for that purpose. Cementing hip prosthesis is falling out of favor among orthopedic surgeons worldwide. The trend toward un-cemented hip arthroplasty is not well supported in the current literature.

Hip Fracture Risk Assessment in Elderly and Diabetic Patients: Combining Autonomous Finite Element Analysis and Machine Learning.

Autonomous finite element analyses (AFE) based on CT scans predict the biomechanical response of femurs during stance and sidewise fall positions. We combine AFE with patient data via a machine learning (ML) algorithm to predict the risk of hip fracture. An opportunistic retrospective clinical study of CT scans is presented, aimed at developing a ML algorithm with AFE for hip fracture risk assessment in type 2 diabetic mellitus (T2DM) and non-T2DM patients. Abdominal/pelvis CT scans of patients who experienced a hip fracture within 2 years after an index CT scan were retrieved from a tertiary medical center database. A control group of patients without a known hip fracture for at least 5 years after an index CT scan was retrieved. Scans belonging to patients with/without T2DM were identified from coded diagnoses. All femurs underwent an AFE under three physiological loads. AFE results, patient's age, weight, and height were input to the ML algorithm (support vector machine [SVM]), trained by 80% of the known fracture outcomes, with cross-validation, and verified by the other 20%. In total, 45% of available abdominal/pelvic CT scans were appropriate for AFE (at least 1/4 of the proximal femur was visible in the scan). The AFE success rate in automatically analyzing CT scans was 91%: 836 femurs we successfully analyzed, and the results were processed by the SVM algorithm. A total of 282 T2DM femurs (118 intact and 164 fractured) and 554 non-T2DM (314 intact and 240 fractured) were identified. Among T2DM patients, the outcome was: Sensitivity 92%, Specificity 88% (cross-validation area under the curve [AUC] 0.92) and for the non-T2DM patients: Sensitivity 83%, Specificity 84% (cross-validation AUC 0.84). Combining AFE data with a ML algorithm provides an unprecedented prediction accuracy for the risk of hip fracture in T2DM and non-T2DM populations. The fully autonomous algorithm can be applied as an opportunistic process for hip fracture risk assessment. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Physician-Patient Communication Course: When the Inauguration of a New Israeli Medical School Coincided with COVID-19 Pandemic.

Purpose: The curriculum of the Adelson School of Medicine at Ariel University, the newly established sixth medical school in Israel, includes a simulation center-based extended course on physician-patient communication, aiming to help students master the core competency of interpersonal and communication skills. For more than a year following the emergence of the COVID-19 pandemic, the school suspended most face-to-face (F2F) encounters, transforming most teaching activities to remote platforms. The paper outlines the ways we adapted teaching of this course to these circumstances, the reactions of students and mentors to the changes and results of 1st year students' survey. Methods: During the lockdown in the first year 48 of 70 first-year students participated in a voluntary anonymous online evaluation of the course assessing motivation to become a physician; perceptions, feelings and attitudes towards the communication course, and advantages and disadvantages of online and F2F medical interviews. Results: 46.1% of the responding students reported that the pandemic strengthened their desire to become physicians. 56.3% claimed that they were able to a relatively large extent to empathize with COVID-19 patients who were exposed to the virus; 79.1% viewed their mentors as positive role models of communication skills. The students were able to receive and offer social support to their peers. They evaluated very highly the short instructional videos produced by the faculty. Conclusion: During the lockdown, the respondents generally indicated positive attitudes towards the communication course, the mentors and the inclusion of physician-patient communication as a topic in medical education. The students and mentors reported many disadvantages and few advantages of remote learning. Yet inevitably remote learning including online-based simulations is a step towards preparations for future practice within virtual medical care and telemedicine. The limitations of this study include the cross-sectional design, small sample size and self-reporting.

The effects of direct factor Xa inhibitor (Rivaroxaban) on the human osteoblastic cell line SaOS2.

Thromboprophylaxis reduces the risk of surgery-related deep vein thrombosis, but anticoagulants were associated with systemic osteoporosis, a known risk factor for poor fracture healing. Rivaroxaban (XARELTO(®)) is a novel anticoagulant with specific ability to inhibit factor Xa, a serine endopeptidase, which plays a key role in coagulation. This study investigated the direct effects of rivaroxaban on bone biology using an in vitro cell culture model from the human female osteoblastic cell line SaOS2. Cells at subconfluence were treated for 24 hr with different concentrations of rivaroxaban and analyzed for DNA synthesis and creatine kinase- and alkaline phosphatase-specific activities, and were treated 21 days for analyzing mineralization. Rivaroxaban (0.01-50 µg/ml) dose-dependently inhibited up to 60% DNA synthesis of the cells. Creatine kinase-specific activity was also inhibited dose-dependently to a similar extent by the same concentrations. Alkaline phosphatase-specific activity was dose-dependently inhibited but only up to 30%. Cell mineralization was unaffected by 10 µg/ml rivaroxaban. This model demonstrated a significant rivaroxaban-induced reduction in osteoblastic cell growth and energy metabolism, and slight inhibition of the osteoblastic marker, alkaline phosphatase, while osteoblastic mineralization was unaffected. These findings might indicate that rivaroxaban inhibits the first stage of bone formation but does not affect later stages (i.e., bone mineralization).

Do weight-bearing films affect decision making in hallux valgus surgery?

Hallux valgus is a complex deformity of the first ray and forefoot that can be surgically treated using different procedures and osteotomies. Preoperative planning includes anteroposterior and lateral plain films. The effect of weight-bearing on the results of the standardized measurements is still the subject of debate. We evaluated the effect of weight-bearing on the results of measurements and decision making by expert evaluators. A total of 21 foot and ankle surgeons were given weight-bearing and non-weight-bearing anteroposterior plain foot films of patients with hallux valgus. They were asked to measure 3 standard angles and then to select the most appropriate procedure from a short list. Using a paired Student's t test, no difference in the angles measured nor in the procedures chosen was detected between the weight-bearing and non-weight-bearing films. Although it is generally accepted that decisions regarding the treatment of hallux valgus should be based on plain weight-bearing films, in the present study, we established that non-weight-bearing films can reliably be used to choose the surgical procedure.

Septic arthritis of the knee following intraarticular injections in elderly patients: report of six patients.

BACKGROUND: Intraarticular injections for the local treatment of osteoarthritis are widely used in the office or hospital setting. Septic arthritis is a potential catastrophic complication of intraarticular injection, as bacterial arthritis of any cause is associated with up to 15% mortality and residual impairment of joint function in up to 50% of survivors. There is lack of evidence regarding the precautions that should be taken to avoid such a complication, as well as how often it is encountered. OBJECTIVES: To report our experience with the clinical presentation, diagnosis and treatment of knee septic arthritis following intraarticular injections. METHODS: We followed six patients who were admitted to the hospital and underwent surgery for the treatment of pyogenic arthritis following injection to the knee joint in outpatient clinics. RESULTS: All but one patient were over 70 years old with comorbidities. Three patients were injected with steroid preparations and three with hyaluronic acid several days before admission. In all six patients the infection was treated surgically and three of them had undergone more than one operation during their hospitalization. Four of the six patients were treated by means of an open arthrotomy and synovectomy, and the other two were treated successfully with arthroscopic lavage and synovectomy. One patient underwent an above-knee amputation due to septic shock and died after several days. CONCLUSIONS: Despite the rarity of this complication, surgeons must be aware of the possibility of pyogenic arthritis when administering injections, especially in elderly patients with serious underlying medical conditions.

Fractures of the distal humerus in elderly patients treated with a ring fixator.

The aim of distal humerus fracture treatment is articular surface reduction and stable fixation for early mobilisation and rehabilitation. This is usually performed by open reduction and internal fixation with plates. In the elderly osteoporotic patient this treatment is difficult to achieve due to fixation failure in fragile bone. We present our experience with treatment by closed reduction and external fixation with a non-bridging ring fixator in distal humerus fractures in elderly patients. There were ten females, aged 70-89 (average 78.4). Fracture types (AO/ASIF) included three supracondylar fractures (type A) and seven intercondylar fractures (type C). All patients were treated by closed reduction and external fixation with a non-bridging ring fixator of the distal humerus and immediate postoperative mobilisation of the elbow. External fixation was removed on an average of 72 days (range 62-90). All fractures united. Average time to union was 56 days. Average range of movement at six months was 22° extension lag (range 15°-30°) and 115° flexion (range 110°-120°). Complications included one patient with transient radial palsy and one patient with a superficial decubitus ulcer on the chest wall from the hardware. Minimally invasive treatment by closed reduction and external fixation with a ring fixator is effective for treatment of fractures of the distal humerus in elderly patients with osteoporotic bone. This treatment enables immediate mobilisation of the elbow, and allows return to function. It should be considered an alternative to open reduction and internal fixation or total elbow replacement.