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Evan L Flatow

Publications and source records attributed to Evan L Flatow.

At least 19 recordsLinked to original sources
PubMed2007

Novel procedure for high-fidelity tendon histology.

A novel method to obtain high-quality histologic sections of rat tendon for light microscopic study is presented. This approach utilizes non-deleterious dehydrating and clearing solvents and a hydrophobic acrylic (methyl methacrylate) resin. This methodology avoids processing and microtomy artifacts common with routine paraffin wax techniques and overcomes specimen size limitations associated with hydrophilic (e.g., glycol methacrylate) resin histologic methods. These novel histologic processing techniques facilitate the reliable assessment of tendons' cellular and matrix components and can be readily adapted to morphologic studies of damage, healing, and repair.

Acrylic Resins↗
PubMed2006

Outcomes after arthroscopic rotator cuff repairs.

Recently, advances in arthroscopic techniques have allowed shoulder surgeons to perform fully arthroscopic repair of full-thickness tears. Outcome data have shown that improvement is inconsistent between studies. We performed a retrospective review of 105 consecutive patients who underwent arthroscopic rotator cuff repair from 1999 to 2002. Preoperative and postoperative evaluation consisted of a history, questionnaire, and examination to determine American Shoulder and Elbow Surgeons, Constant, and visual analog pain scores. Complete data were available for a minimum of 12 months (range, 12-45 months) for 71 patients. Increases in range of motion and outcome scores and associated reductions in visual analog scores were all significant. With massive tears, scores and pain were significantly improved. Arthroscopic rotator cuff repair reliably improves functional deficits and pain regardless of tear size. Smaller tears yield significant improvement in American Shoulder and Elbow Surgeons, Constant, and pain scores. Functional improvement was seen with massive tears, but gains in strength and motion were less dramatic.

Adult↗
PubMed2006

The inferior glenohumeral ligament: a correlative investigation.

The inferior glenohumeral ligament (IGHL) was investigated by correlating the biomechanical properties, biochemical composition, and histologic morphology of its 3 anatomic regions (superior band, anterior axillary pouch, and posterior axillary pouch) in 8 human cadaveric shoulders. The overall biochemical composition of the IGHL appeared similar to other ligaments, with average water content of 80.9 +/- 2.5%, collagen content of 80.0 +/- 9.2%, and crosslinks of 0.715 +/- 0.13 mol/mol collagen. The proteoglycan content was highest in the superior band (2.73 +/- 0.7 mg/g dry weight) and may, in part, explain its viscoelastic behavior. Histologic analysis demonstrated longitudinally organized fiber bundles that were more uniform in the mid-substance but more interwoven and less uniformly oriented near the insertion sites. The superior band had the most pronounced fiber bundle interweaving, while crimping was more evident in the anterior axillary pouch. Elastin was identified in each of the regions. Tensile testing demonstrated a trend toward higher ultimate tensile stress (16.9 +/- 7.9 MPa) and tensile modulus (130.3 +/- 47.9 MPa) in the superior band compared to the axillary pouch. The mean ultimate tensile strain of the IGHL was 16.8 +/- 4.6%. These complex IGHL properties may help to explain its unique functions in stabilizing the shoulder in different arm positions and at different rates of loading, including the failure patterns seen clinically, as in Bankart lesions (insertion site) versus capsular stretching (ligament substance).

Aged↗
PubMed2006

The outcome of resection shoulder arthroplasty for recalcitrant shoulder infections.

Postarthroplasty infection is a devastating complication. In some patients, virulent pathogens or poor health complicate reconstruction. Resection arthroplasty is a viable option in such cases. Seven patients with resection arthroplasty following infection after shoulder arthroplasty were reviewed retrospectively at an average 20- month follow-up (range, 12-41). Average time between the initial procedure and the first debridement was 59.5 months (4-151 months). The average number of debridements was 2.2 per patient (range, 1-4 procedures). There were no complications, no recurrence of deep infection, no nerve damage, and no fractures. All patients were able to reach the opposite axilla, their backpocket and perineum, and their mouth. All but 1 patient were satisfied with their result. No patient had a satisfactory outcome via Neer's criteria. Resection arthroplasty is a reasonable salvage option for patients who are not good candidates for prosthetic reimplantation. This yields patients who can reliably perform basic activities of daily living.

Aged↗
PubMed2006

Variability in tendon and knee joint biomechanics among inbred mouse strains.

Hereditary factors are thought to be responsible for impaired tendon function and joint laxity. The present study investigated the genotypic variability of knee laxity and stiffness and tendon mechanical and geometric properties among 16-week-old female A/J, C57BL/6J (B6), and C3H/HeJ (C3H) inbred mice. In one group of mice, knee mechanics were quantified using a custom loading apparatus enabling translation of the tibia against a stationary femur. In a second group, flexor digitorum longus and Achilles tendons from the left hind limb underwent biomechanical testing, while those of the contralateral limb were analyzed histologically for determination of cross-sectional area. Our results demonstrate that tendon and joint mechanics varied significantly among the inbred mouse strains, indicating that biomechanical properties are genetically determined. A/J mouse knees exhibited greater laxity (p < 0.001) and lower stiffness (p < 0.001) compared to those of the B6 and C3H mice. The genotypic differences in whole joint properties were similar to those of the tendons' structural biomechanical traits. Although body mass did not differ (p > 0.2) among the three strains, significant genotypic differences were found at the whole tendon, material quality, and morphological levels of the tissue hierarchy. Furthermore, genetic regulation of tendon mechanical properties varied with anatomic site. Patterns of genotypic differences in tendon size were not consistent with those of biomechanical properties, suggesting that unique combinations of structural and compositional factors contribute to tendon growth, adaptation, and development. Therefore, the three inbred strains constitute a useful experimental model to elucidate genetic control of structure-function relationships in normal and healing tendons and ligaments.

Achilles Tendon↗
PubMed2005

Inhomogeneous mechanical behavior of the human supraspinatus tendon under uniaxial loading.

Disorders of the rotator cuff, particularly tears of the rotator cuff tendons, cause significant shoulder disability. Among numerous factors thought to be responsible for the initiation and progression of supraspinatus tears are those related to the tendon's biomechanical properties. We hypothesized that in supraspinatus tendons subjected to tensile loading a strain gradient (difference) exists between the articular and bursal tendon surfaces, that regional strain differences exist on each of these two tendon surfaces, and that tendon surface strains vary with glenohumeral abduction. To test these hypotheses, the intrinsic inhomogeneous deformational characteristics of the articular and bursal surfaces of eight intact human cadaveric supraspinatus tendons were studied at three glenohumeral abduction angles using a novel multiple strain measuring system which simultaneously recorded surface marker displacements on two opposing soft tissue surfaces. Under applied tensile loads, the articular surface exhibited greater strain at 22 degrees (7.4+/-2.6% vs. 1.3+/-0.7%, p=0.0002) and 63 degrees (6.4+/-1.6% vs. 2.7+/-1.2%, p=0.0001) whereas the bursal surface exhibited greater strain at 90 degrees (7.6+/-2.8% vs. 4.9+/-0.4%, p=0.013). At all abduction angles, insertion strains were higher than those of the mid-tendon and tendon-muscle junction regions. The existence of inhomogeneous surface strains in the intact supraspinatus tendon demonstrates that intratendinous shear occurs within the tendon. The higher strain on the articular side of the tendon, especially at the insertion region, suggests a propensity for tears to initiate in the articular tendinous zone.

Adult↗
PubMed2005

Incidence of early radiolucent glenoid lines in patients having total shoulder replacements.

UNLABELLED: Glenoid loosening is the most common long-term complication occurring after total shoulder replacement. Imprecise cement technique and glenoid preparation may result in early radiolucent glenoid line formation. Early radiolucent lines may indicate inadequate initial fixation, which may contribute to early loosening. Improved cement techniques, refined instrumentation, and glenoid component design all may reduce early radiolucent lines. In our study, postoperative anteroposterior and axillary radiographs were obtained after 68 total shoulder replacements done by one surgeon using either an old free-hand, manual packing technique before November 1998 (n = 28) or a new instrument preparation and pressurization technique since November 1998 (n = 40). Three orthopaedic surgeons blindly reviewed the radiographs for the presence and thickness (mm) of radiolucent lines. The newer instrumented pressurization group had a lower incidence of radiolucent lines than the old manually packed group. In the new subgroup, pegged components had a lower incidence of radiolucent lines than keeled components. The incidence of radiolucent lines seems to be reduced using specially designed instruments, new glenoid designs, and modern cement techniques, which may lead to reduced long-term glenoid loosening. LEVEL OF EVIDENCE: Therapeutic study, Level III-2 (retrospective cohort study). See the Guidelines for Authors for a complete description of levels of evidence.

Adult↗
PubMed2005

Pediatric shoulder trauma.

Pediatric shoulder trauma is relatively uncommon. Injuries requiring surgical intervention are even rarer. However, it is important for the practicing orthopaedic surgeon to differentiate nonoperative injuries from the urgent and potentially operative injuries. Missing such an injury in the pediatric population could be potentially life threatening or lead to long-term disability. Posterior sternoclavicular dislocations should be differentiated from medial clavicular physeal injuries and promptly reduced. Open fractures or neurovascular threatening fractures should be attended to immediately. Severely displaced proximal physeal humerus fractures in the older child often have a better long-term outcome after anatomic reduction. Finally, although glenohumeral dislocations, once reduced, are not life threatening or limb threatening, they do have a very high incidence of recurrence in adolescent patients. This should be kept in mind when formulating the treatment plan. If these overall treatment recommendations and plans are adhered to, the majority of pediatric shoulder trauma will result in a good outcome.

Adolescent↗
PubMed2005

Interscalene regional anesthesia for shoulder surgery.

BACKGROUND: Despite a trend toward the use of regional anesthesia for orthopaedic procedures, there has been resistance to the use of interscalene regional block for shoulder surgery because of concerns about failed blocks and potential complications. METHODS: We retrospectively reviewed the cases of 568 consecutive patients who had shoulder surgery under interscalene regional block in a tertiary-care, university-based practice with an anesthesiology residency program. The blocks were performed by a group of anesthesiologists who were dedicated to the concept of regional anesthesia in their practice. Complete anesthetic and orthopaedic records were available for 547 patients. The surgical procedure, planned type of anesthesia, occurrence of block failure, and the presence of complications were noted. RESULTS: Of the 547 patients, 295 underwent an arthroscopic procedure and 252 (including eighty who had an arthroplasty) underwent an open procedure. General anesthesia was the initial planned choice for sixty-nine patients because of the complexity or duration of the procedure, the anatomic location, or patient insistence. Thirty-four of the sixty-nine patients also received an interscalene regional block. Interscalene regional block alone was planned for 478 patients. A total of 462 patients (97%) had a successful block whereas sixteen required general anesthesia because the block was inadequate. The success of the block was independent of the type or length of the surgery. No patient had a seizure, pneumothorax, cardiac event, or other major complication. Twelve (2.3%) of the 512 patients who had a block had minor complications, which included sensory neuropathy in eleven patients and a complex regional pain syndrome that resolved at three months in one patient. For ten of the eleven patients, the neuropathy had resolved by six months. CONCLUSIONS: Interscalene regional block provides effective anesthesia for most types of shoulder surgery, including arthroplasty and fracture fixation. When administered by an anesthesiologist committed to and skilled in the technique, the block has an excellent rate of success and is associated with a relatively low complication rate.

Arthroplasty↗
PubMed2005

Septic arthritis of the glenohumeral joint: a review of 23 cases.

Infection of the glenohumeral joint is an uncommon yet devastating condition. The objective of this study was to review the incidence, risk factors, presentation, and treatment for this disorder. Twenty-three culture-positive cases of septic arthritis of the glenohumeral joint were identified and treated at the authors' institution between 1986 and 2000. Eighty-seven percent of patients had at least one serious systemic illness, and on average had two. Fifty-two percent had a different primary site of infection identified. Staphylococcus aureus was identified as the infectious organism in 70% of cases, 17% of which were found to be methicillin-resistant S. aureus. Patients admitted to the orthopedic service were more likely to undergo surgical treatment. Patients treated surgically had shorter hospital stays than those treated with serial aspirations alone. Shoulder infections affect patients who are older and have multiple systemic diseases. Surgical treatment of shoulder infections, when compared to aspiration alone, is associated with a shorter hospital stay. Glenohumeral infection is a debilitating affliction even when control of the infection can be achieved.

Adult↗
PubMed2004

Multidirectional instability: surgical decision making.

Although previous authors have described multidirectional instability of the shoulder, it was not until 1980 that Neer and associates solidified the current understanding and treatment of inferior and multidirectional instability. They emphasized the importance of differentiating this condition from the more common unidirectional instabilities and introduced the concept of an inferior capsular shift to globally tension the capsule anteriorly, inferiorly, and posteriorly, while thickening and reinforcing it on the side of greatest instability (i.e., anterior or posterior). Since the time of this initial description, the diagnosis and treatment of multidirectional instability has been fraught with difficulty and confusion. More recently, the advent of shoulder arthroscopy has blazed the trail for minimally invasive techniques to correct multidirectional instability, including arthroscopic thermal capsulorrhaphy and suture plication. However, despite strong opinions regarding these surgical techniques, when comparing open approaches to arthroscopic techniques for the treatment of multidirectional instability, long-term outcomes of arthroscopic techniques have yet to replicate those of open surgery.

Arthroscopy↗
PubMed2003

Management of glenohumeral arthritis: a role for arthroscopy?

When nonoperative measures fail in the treatment of glenohumeral arthritis, arthroscopy has emerged as a viable therapeutic option. It is valuable as a diagnostic and therapeutic intervention and has a low morbidity and low complication rate. Arthroscopic techniques can be performed in the younger patient or athlete wishing to delay arthroplasty or in the elderly patient with associated comorbidities wishing to avoid a larger operation. In those with inflammatory arthropathies, arthroscopy with associated debridement and synovectomy can relieve pain, improve function, and delay progression of the disease. In the athlete and young patient with osteoarthritis, arthroscopy allows recognition and treatment of coexisting pathologies in which procedures such as subacromial decompression and capsular release have proven to be of benefit. Arthroscopic debridement, abrasion arthroplasty, and microfracture techniques seem to be of some benefit; however, it remains unclear who the ideal candidate is. Overall it is generally viewed that patients improve and benefit most when intervention is early in the course of the disease. Although the role of arthroscopy in the treatment of glenohumeral arthritis is evolving, in certain situations and patients it is thus a viable option and another tool in the armamentarium of the orthopedic surgeon.

Arthritis↗
PubMed2003

Anatomy of the posterior rotator interval: implications for cuff mobilization.

Release of the posterior rotator interval between the supraspinatus and infraspinatus tendons may be necessary to obtain appropriate mobilization for an anatomic rotator cuff repair. Ten cadaver shoulders were dissected to expose the region between the infraspinatus and supraspinatus from the spinoglenoid notch to the greater tuberosity. Measurements were made from the spinoglenoid notch to the glenoid rim, the glenoid rim to the confluence of the supraspinatus and infraspinatus musculotendinous junction, and from the confluence of the tendons to the insertion on the humerus. The histologic features of the posterior rotator interval were examined. The posterior rotator interval is a clear structure, consisting of the glenohumeral capsule medially, which fuses with the supraspinatus and infraspinatus tendons laterally. The average length of the posterior rotator interval was 77.8 mm which includes the distance from the spinoglenoid notch to the glenoid rim (25 mm; standard deviation, 2.89 mm; range, 21-28 mm), from the glenoid to the tendon confluence (25 mm; standard deviation, 1.95 mm; range, 21-28 mm), and from the tendon confluence to insertion (28 mm; standard deviation, 2.36 mm; range, 24-31 mm). Release of the posterior rotator interval can be important to realign the supraspinatus tendon if it is retracted and scarred at its posterior edge.

Arthroscopy↗
PubMed2003

Transitioning to arthroscopic rotator cuff repair: the pros and cons.

There has been much recent enthusiasm regarding complete arthroscopic rotator cuff repair, and it is becoming apparent that, for many, this newer technique may be a preferable alternative to the more traditional mini-open rotator cuff repair. Several short-term studies have demonstrated that complete arthroscopic repair has excellent results comparable with those of mini-open repair, which is also an excellent technique. The choice of which procedure may be better for an individual patient or surgeon can be based on a variety of considerations, including the patient's expectations, the pathoanatomy of the cuff, and the surgical experience of the surgeon. The relative merits and disadvantages of arthroscopic rotator cuff repair are discussed on the basis of those considerations. When a surgeon is deciding which procedure to perform, it is important that the basic principles of rotator cuff repair not be compromised and that he or she perform the procedure that is most reproducible given his or her level of experience; however, for those who are now utilizing miniopen repair, arthroscopic repair may have important advantages and may be worth pursuing in the future. If a surgeon chooses to obtain the skills necessary to perform a complete arthroscopic repair, performance of the mini-open procedure offers an excellent opportunity to make an orderly transition.

Arthroscopy↗
PubMed2003

[Close needling for the treatment of calcifying tendinitis].

OBJECTIVE: To study the effect of close needling in the treatment of calcifying tendonitis. METHODS: Seventeen patients with calcifying tendonitis who had received close needling treatment were followed-up for 9.3 months on average. An 18-gauge or 16-gauge needle was used during needling. X-ray examination was given 4, 6, 8 and every 4 weeks after needling. SST (simple shoulder test) questionnaire, ASES (American Shoulder & Elbow Surgeon) score, constant-Murley score and UCLA score were adopted for evaluation before and after treatment. RESULTS: Calcium deposition disappeared within 4 - 20 weeks mean 9.4 weeks in 15 of the 17 patients after needling for 1 - 3 times. Average ASES score before treatment was 47.7 (34 - 59), forward elevation was 90 degrees (70 degrees - 100 degrees ), external rotation was 15 degrees (0 degrees - 30 degrees ), and internal rotation was L3-4 (L1-buttock). Average constant-Murley score before treatment was 44.6 (34 - 54), UCLA score was 11.6 (8 - 15), and numbers of questions for "yes" in SST questionnaire was 3.4 (2 - 5). After needling the average ASES score was 87.1 (72 - 91), forward elevation was 143.5 degrees (120 degrees - 160 degrees ), external rotation was 40 degrees (30 degrees - 50 degrees ), internal rotation was T(8)-T(9), constant-Murley score was 87.8 (64 - 94), UCLA score was 29.5 (19 - 33), and numbers of questions for "yes" in SST questionnaire was 9.1 (6 - 12). Significant difference was found between before and after needling (ASES: P < 0.01, forward elevation, external rotation and internal rotation: P < 0.01, constant-Murley: P < 0.01, UCLA: P < 0.01, SST: P < 0.01). CONCLUSIONS: Close needling is an effective method for the treatment of calcifying tendonitis. Symptoms and disability are greatly relieved non-surgically in most of patients. Care should be taken in differential diagnosis of degenerative calcification in chronic rotator cuff disease.

Adult↗
PubMed2002

Controversial topics in shoulder arthroscopy.

This is a review of the symposium entitled Controversial Topics in Shoulder Arthroscopy 2001, presented at the Arthroscopy Association of North America 20th Annual Meeting in Seattle, Washington in April of 2001. The covered topics include micro-instability, partial thickness rotator cuff tears, pathology of the biceps tendon, and thermal capsulorrhaphy.

Adolescent↗
PubMed2002

Comparison of intra-articular lidocaine and intravenous sedation for reduction of shoulder dislocations: a randomized, prospective study.

BACKGROUND: Acute anterior glenohumeral dislocations have been commonly treated with closed reduction and the use of intravenous sedation. Recently, the use of intra-articular lidocaine has been advocated as an alternative to sedation, since intravenous access and patient monitoring are not required. The purpose of this study was to evaluate the value of local anesthesia compared with that of the commonly used intravenous sedation during the performance of a standardized reduction technique. METHODS: In a prospective, randomized study, skeletally mature patients with an isolated glenohumeral joint dislocation and no associated fracture were randomized to receive either intravenous sedation or intra-articular lidocaine to facilitate reduction of the dislocation. Reduction was performed with the modified Stimson method. The two groups were compared with regard to the rate of successful reduction, pain as rated on a visual analog scale, time required for the reduction, time from the reduction until discharge from the emergency department, and cost. RESULTS: Thirty patients were enrolled in the study. Five (two in the lidocaine group and three in the sedation group) required scapular manipulation in addition to the Stimson technique to reduce the dislocation. The lidocaine group spent significantly less time in the emergency department (average time, seventy-five minutes compared with 185 minutes in the sedation group, p < 0.01). There was no significant difference between the two groups with regard to pain (p = 0.37), success of the Stimson technique (p = 1.00), or time required to reduce the shoulder (p = 0.42). The cost of the intravenous sedation was $97.64 per patient compared with $0.52 for use of the intra-articular lidocaine. CONCLUSIONS: Use of intra-articular lidocaine to facilitate reduction with the Stimson technique is a safe and effective method for treating acute shoulder dislocations in an emergency room setting. Intra-articular lidocaine requires less money, time, and nursing resources than does intravenous sedation to facilitate reduction with the Stimson technique.

Adolescent↗