A site to transform Pubmed publications into these bibliographic reference formats: ADS, BibTeX, EndNote, ISI used by the Web of Knowledge, RIS, MEDLINE, Microsoft's Word 2007 XML.

Gabriel Agar - Top 30 Publications

The Proprioceptive System Regulates Morphologic Restoration of Fractured Bones.

Successful fracture repair requires restoration of bone morphology and mechanical integrity. Recent evidence shows that fractured bones of neonatal mice undergo spontaneous realignment, dubbed "natural reduction." Here, we show that natural reduction is regulated by the proprioceptive system and improves with age. Comparison among mice of different ages revealed, surprisingly, that 3-month-old mice exhibited more rapid and effective natural reduction than newborns. Fractured bones of null mutants for transcription factor Runx3, lacking functional proprioceptors, failed to realign properly. Blocking Runx3 expression in the peripheral nervous system, but not in limb mesenchyme, recapitulated the null phenotype, as did inactivation of muscles flanking the fracture site. Egr3 knockout mice, which lack muscle spindles but not Golgi tendon organs, displayed a less severe phenotype, suggesting that both receptor types, as well as muscle contraction, are required for this regulatory mechanism. These findings uncover a physiological role for proprioception in non-autonomous regulation of skeletal integrity.

The Proprioceptive System Masterminds Spinal Alignment: Insight into the Mechanism of Scoliosis.

Maintaining posture requires tight regulation of the position and orientation of numerous spinal components. Yet, surprisingly little is known about this regulatory mechanism, whose failure may result in spinal deformity as in adolescent idiopathic scoliosis. Here, we use genetic mouse models to demonstrate the involvement of proprioception in regulating spine alignment. Null mutants for Runx3 transcription factor, which lack TrkC neurons connecting between proprioceptive mechanoreceptors and spinal cord, developed peripubertal scoliosis not preceded by vertebral dysplasia or muscle asymmetry. Deletion of Runx3 in the peripheral nervous system or specifically in peripheral sensory neurons, or of enhancer elements driving Runx3 expression in proprioceptive neurons, induced a similar phenotype. Egr3 knockout mice, lacking muscle spindles, but not Golgi tendon organs, displayed a less severe phenotype, suggesting that both receptor types may be required for this regulatory mechanism. These findings uncover a central role for the proprioceptive system in maintaining spinal alignment.

Prospective Comparison between Remnant-Preserving Augmentation and Double-Bundle Reconstruction in Anterior Cruciate Ligament Tears.

The debate continues regarding the best way to manage partial anterior cruciate ligament (ACL) tears.


Patellofemoral instability is a complex anatomical phenomena that requires deep understanding. The cause for instability could be a result of an anatomical defect or a soft tissue pathology. A thorough patient history, physical examination and imaging are paramount for a correct diagnosis and for deciding on the correct treatment. The proper treatment is often debatable. Conservative treatment is suitable for acute dislocation but has a high failure rate in chronic instability, which usually necessitates surgical treatment. The common surgical treatments today focus on fixing anatomical defects, relieving patients' symptoms of instability and giving them the opportunity to return to the level of activity suitable for them. In this literature review we summarize the relevant anatomy, biomechanics, clinical evaluation and treatment options for patellofemoral instability.

The Long-Term Outcome After Varus Derotational Osteotomy for Legg-Calvé-Perthes Disease: A Mean Follow-up of 42 Years.

Varus derotational osteotomy (VDRO) is one of the most common surgical treatments for Legg-Calvé-Perthes disease, yet its long-term results have not been fully assessed. We aimed to determine the long-term clinical and radiographic outcomes following VDRO.

Mini-Invasive floating metatarsal osteotomy for resistant or recurrent neuropathic plantar metatarsal head ulcers.

Patients with peripheral neuropathy and pressure under a relatively plantar deviated metatarsal head frequently develop plantar foot ulcers. When conservative management with orthotics and shoes does not cure the ulcer, surgical metatarsal osteotomy may be indicated to relieve the pressure and enable the ulcer to heal. The purpose of this study is to evaluate the use of a mini-invasive floating metatarsal osteotomy in treating recalcitrant ulcers or recurrent ulcers plantar to the metatarsal heads in patients with diabetes mellitus (DM) related neuropathy.

Clinical presentation and imaging results of patients with symptomatic gluteus medius tears.

Greater trochanteric pain syndrome (GTPS) is a common complaint. Recently, it has become well recognized that tendinopathy and tears of the gluteus medius (GM) are a cause of recalcitrant GTPS. Nevertheless, the clinical syndrome associated with GM tears is not fully characterized. We characterize the clinical history, findings on physical examination, imaging and intraoperative findings associated with symptomatic GM tears. Forty-five patients (47 hips) who underwent GM repair for the diagnosis of tear were evaluated. Pain was estimated on the visual analog scale (VAS) and hip-specific scores were administered to assess functional status. The imaging modalities were reviewed and intra operative findings were recorded. The average patient age was 54 years (17-76), 93% were females. Symptom onset was commonly insidious (75%) and the average time to diagnosis was 28 months (2-240). The most common pain location was the lateral hip (75%). The average pre-surgery VAS and modified Harris Hip Score were 6.65 (0-10) and 55.5 (12-90), respectively. All patients had pathological findings on magnetic resonance angiogram (MRA) ranging from tendinosis to complete tears of the GM tendon. There was a discrepancy between MRA interpretation by a radiologist and findings during surgery. Hip abductor tears are an under-recognized cause of hip pain and hip symptomatology. In this study, we further characterize the clinical presentation of this entity. The data we present here may facilitate early diagnosis, early orthopedic care and avoid unnecessary prolonged patient sufferings.

Toe-Sparing Surgery for Neuropathic Toe Ulcers With Exposed Bone or Joint in an Outpatient Setting: A Retrospective Study.

The purpose of this study was to review the results of aggressive surgical debridement of neuropathic toe ulcers with exposed bone or joint. We identified patients with a single toe ulcer with exposed bone or joint that had been operated on in an outpatient setting. The surgery had included aggressive debridement and was performed using a small curette and rongeur, followed by oral antibiotic treatment at home. Success was defined as complete healing with no recurrence 6 months after full wound closure and epitheliazation was achieved. Twenty-five patients with neuropathic toe ulcers (72% male) had a total of 26 primary operations. Their mean age was 60 ± 12 years. In 22 patients, the neuropathy resulted from diabetes mellitus of 17 ± 9 years' duration. The mean ulcer duration was 6 weeks (range 1-24). The mean number of visits per patient was 6.5 (range 3-20). The ulcers closed in a median of 5 weeks (8 ± 6 weeks, range 3-24 weeks, Q1-Q3 4-10 weeks). At 6 months, 3 (11.5%) patients had needed a toe amputation for infection or necrosis that could not be controlled. None needed a major amputation or hospitalization related to the ulcer. Toe-sparing surgery is feasible and in a select population can have a high success rate (88%), even though it does dictate more dedicated patient care.

The Sphygmomanometer Pain Test: A Simple Method for Identifying Patients at Risk of Excessive Pain after Total knee Arthroplasty.

Despite the overall success of total knee arthroplasty (TKA), a relatively large proportion of patients remain dissatisfied with the outcome. We hypothesized that patients with a lower threshold for pain were more likely to have worse outcomes after TKA.

Severe vascular complications and intervention following elective total hip and knee replacement: A 16-year retrospective analysis.

Iatrogenic vascular injuries associated with elective orthopaedic joint procedures are relatively rare, however when they do occur they carry a risk of significant morbidity and mortality. The aim of this study was to investigate the incidence of vascular complications and resultant need for specialist intervention following elective total hip replacement (THR) and total knee replacement(TKR).

A novel self-care biomechanical treatment for obese patients with knee osteoarthritis.

To examine the effect of a novel biomechanical, home-based, gait training device on gait patterns of obese individuals with knee OA.

Comparison of knee SPECT and MRI in evaluating meniscus injuries in soldiers.

Medical evaluation of a suspected meniscus injury begins with a history-taking and physical examination. Suspected meniscus injuries not responding to treatment are usually sent for imaging to confirm the diagnosis before arthroscopy. Tc-MDP bone single photon emission computed tomography (SPECT) scan has been suggested as an alternative to magnetic resonance imaging (MRI) in evaluating suspected knee meniscus tears.

An unusual case of leg pain in a competitive cyclist: a case report and review of the literature.

Cycling has become a popular recreational and competitive sport. The number of people participating in the sport is gradually increasing. Despite being a noncontact, low-impact sport, as many as 85% of athletes engaged in the sport will suffer from an overuse injury, with the lower limbs comprising the majority of these injuries. Up to 20% of all lower extremity overuse injuries in competitive cyclists are of a vascular source. A 39-year-old competitive cyclist had a 5-year history of thigh pain during cycling, preventing him from competing. The patient was eventually diagnosed with external iliac artery endofibrosis. After conservative treatment failed, the patient underwent corrective vascular surgery with complete resolution of his symptoms and return to competitive cycling by 1 year. Since its first description in 1985, there have been more than 60 articles addressing external iliac artery endofibrosis pathology.

Management of chronic exertional compartment syndrome and fascial hernias in the anterior lower leg with the forefoot rise test and limited fasciotomy.

Chronic exertional compartment syndrome can present either as anterolateral lower leg pain or as painful muscle herniation. If an athlete or a soldier wants to continue training, there is no proven effective nonoperative treatment, and fasciotomy of 1 or more of the lower leg muscle compartments is usually recommended. Our clinical protocol differs from most reported ones in the use of the forefoot rise test to increase pressure and provoke pain and our recommending minimal surgery of the anterior compartment only. We present results of surgery based on our clinical management flowchart.

Who is at risk of receiving inadequate care for osteoporosis following fragility fractures? A retrospective study.

Osteoporosis is considered the most common bone disease in humans and the most common cause of fractures.

The case for orthopaedic medicine in Israel.

Musculoskeletal complaints are probably the most frequent reasons for visiting a doctor. They comprise more than a quarter of the complaints to primary practitioners and are also the most common reason for referral to secondary or tertiary medicine. The clinicians most frequently consulted on musculoskeletal problems, and probably perceived to know most on the topic are orthopaedic surgeons. But in Israel, there is significant ambivalence with various aspects of the consultations provided by orthopaedic surgeons, both among the public and among various groups of clinicians, particularly family practitioners and physiotherapists.

Assessing kyphosis with SpineScan: another attempt to reduce our dependence on radiography.

Kyphosis management is mainly conservative, with annual examinations to assess angular progression. This includes physical examination and usually long spine X-rays, notorious for ionizing radiation. Several nonradiological instruments have been devised for this, but none have become popular. SpineScan, a programmed digital inclinometer, has been proved effective for screening kyphoscoliosis.

The outcome of a novel biomechanical therapy for patients suffering from anterior knee pain.

This study was devised to examine the effect of a novel biomechanical therapy for patients suffering from anterior knee pain (AKP).

SPECT versus Planar Scintigraphy as a Clinical Aid in Evaluation of the Elderly with Knee Pain.

Chronic knee pain is a common complaint among the elderly and appears in 30%-40% of the population over the age of 65. This study was performed in order to evaluate correlation between clinical presentation of chronic knee pain and the imaging findings of SPECT and planar bone scintigraphy. Methods. We prospectively recruited 116 patients over the age of 50 who had neither knee surgery nor trauma. Patients were divided into symptomatic and asymptomatic groups. All patients were examined by an experienced orthopedic surgeon; on the same day imaging was performed. Statistical analysis was performed to correlate physical examination findings with planar scintigraphy and SPECT findings and blood pool images. Results. In symptomatic patients, planar scintigraphy correlated significantly (P < 0.01) with the presence of excessive joint fluid, synovial condensation, and decrease in range of motion as measured in extension and flexion and patellar grinding test. SPECT findings correlated with all of the above tests as well as with medial and patellofemoral joint tenderness. Conclusions. We believe a finding of tenderness at the medial articular crease or of the patellofemoral compartment of the knee should be considered an indication for the use of SPECT scintigraphy rather than planar scintigraphy.

Pattern of outsole shoe heel wear in infantry recruits.

The influence of radiofrequency ablation patterns on length, histological and mechanical properties of tendons.

The use of radiofrequency ablation for thermomodulation of connective tissues has gained acceptance with some surgeons. It is now mainly used for shoulder instability, and two techniques are commonly applied - ablation in a uniform pattern (paintbrush) and ablation in a linearly dispersed fashion (grid). The use of these techniques for shrinkage of tendons or cruciate ligaments is not widely accepted but may be utilized in selected cases. We assessed the effects of thermo-modulation via monopolar radiofrequency ablation using these two techniques on the histological and biomechanical properties of rabbit Achilles tendons. 16 paired rabbit achilles tendons were divided into two treatment groups. Using a Monopolar RF device, eight tendons were treated using the paintbrush technique, and eight using the grid technique. The tendons were shrunk to about 90% of their original length, and the paired tendons were used as control. Following thermomodulation, tendons were pulled to tear using the Instron 4502 (Instron, Mass.) device. We found treated tendons were significantly less resistant to tear when compared to control; the average load to failure of the treatment group was 19.4% lower (p=0.05) than the control group values and the average tissue stiffness in the treatment group was 11.3% lower (p=0.051) than the control group. We found a tendency towards a lower resistance to pull in the tendon group treated using the grid technique. Histological analysis demonstrated areas of collagen denaturation correlated to areas of thermomodulation. A random point of failure was found along the tendons in the paintbrush group whereas the typical point of failure in the grid group was located at the treatment point or at its margins. Our findings demonstrate that use of the grid technique in ablation of tendons creates typical failure points (locus minoris resistenci) which bring about failure and alter the biomechanical properties of the thermomodulated tendons. Thermomodulation of tendons may be used efficiently in selected cases but its detrimental effects to the biomechanical attributes of the tissue should be considered.

Sex and body mass index correlate with Western Ontario and McMaster Universities Osteoarthritis Index and quality of life scores in knee osteoarthritis.

To examine the associations of sex, body mass index (BMI), and age with knee osteoarthritis (OA) symptomatic severity.

Efficacy of methylsulfonylmethane supplementation on osteoarthritis of the knee: a randomized controlled study.

Patients with osteoarthritis (OA) take a variety of health supplements in an attempt to reduce pain and improve function. The aim of this study was to determine the efficacy of methylsulfonylmethane (MSM) in treating patients with knee OA.

Can single limb support objectively assess the functional severity of knee osteoarthritis?

There is a lack in objective measurements that can assess the symptoms of knee osteoarthritis (KOA). In a previous study it was shown that pain and function are in higher correlation with the single-limb support gait parameter than with radiographic KOA stage. Single limb support represents a phase in the gait cycle when the body weight is entirely supported by one limb, while the contra-lateral limb swings forward. The purpose of this study was to further examine the relationship between single-limb support and the level of pain and function in patients with KOA. 125 adults with bilateral KOA underwent a physical and radiographic evaluation, and completed the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the SF-36 health survey. Patients walked barefoot at a self-selected speed on a computerized mat. Statistical analysis was used to divide the patients into quintiles based on single-limb support phase value and determine the differences in WOMAC and SF-36 scores between quintiles. Significant differences were found in WOMAC and SF-36 sub-category scores between the single-limb support quintiles. The means of the WOMAC-pain and WOMAC-function sub-categories decreased gradually over single-limb support quintiles (P<0.001), and the means of the SF-36 sub-categories increased gradually over the quintiles (P<0.001). Results show that single-limb support quintiles can help determine the level of pain, function and quality of life in patients with KOA. These results suggest that single-limb support quintiles may be added as an additional scale for generally assessing the symptomatic stage of KOA.

Correlation between single limb support phase and self-evaluation questionnaires in knee osteoarthritis populations.

To investigate the correlation between single limb support (SLS) phase (% of gait cycle) and the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) questionnaire and Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36 Health Survey) in patients with knee osteoarthritis (OA).

The Chondrogenic Potential of Mesenchymal Cells and Chondrocytes from Osteoarthritic Subjects: A Comparative Analysis.

The multipotential nature of stem or progenitor cells apparently makes them the ideal choice for any cell therapy, but this as yet remains to be proven. This study (30 subjects) was designed to compare the potential to repair articular cartilage of chondrocytes taken from different regions in osteoarthritic cartilage with that of mesenchymal stem cells prepared from bone marrow of the same subject.

Chondroprotective effects of a polycarbonate-urethane meniscal implant: histopathological results in a sheep model.

injury or loss of the meniscus generally leads to degenerative osteoarthritic changes in the knee joint. However, few surgical options exist for meniscal replacement. The goal of this study was to examine the ability of a non-degradable, anatomically shaped artificial meniscal implant, composed of Kevlar-reinforced polycarbonate-urethane (PCU), to prevent progressive cartilage degeneration following complete meniscectomy.

Diabetes mellitus as a risk factor for the development of lumbar spinal stenosis.

Diabetes mellitus is a multi-organ disorder affecting many types of connective tissues, including bone and cartilage. Certain skeletal changes are more prevalent in diabetic patients than in non-diabetic individuals. A possible association of diabetes mellitus and lumbar spinal stenosis has been raised.

Differences in gait patterns, pain, function and quality of life between males and females with knee osteoarthritis: a clinical trial.

The aim of this study was to gain a deeper understanding of the gender differences in knee osteoarthritis (OA) by evaluating the differences in gait spatio-temporal parameters and the differences in pain, quality of life and function between males and females suffering from knee OA.

Medial plica syndrome.

Synovial plicae are membranous inward folds of the synovial lining of the knee joint capsula. Such folds are regularly found in the human knee, but most are asymptomatic and of little clinical consequence. However, they can become symptomatic and cause knee pain. In this review, we will discuss medial plica syndrome. Medial plica irritation of the knee is a common source of anterior knee pain. The main complaint is an intermittent, dull, aching pain in the area medial to the patella above the joint line and in the supramedial patellar area. Pain increases with activity, especially when knee flexion and extension are required. Treatment includes physiotherapy, reducing activity, and rest. In cases that do not respond initially to an exercise program, corticosteroid injections and non-steroidal antiinflammatory medication are given. Results of conservative treatment seem to be more appropriate in young patients with a short duration of symptoms. If conservative treatment fails, surgical treatment using arthroscopy is appropriate. During arthroscopy, excision of the whole plica should be achieved.