A 31P NMR study of the interaction of the antitumor active metallocene Cp2MoCl2 with calf thymus DNA.

Treatment of sonicated calf thymus DNA with the antitumor active metallocene Cp2MoCl2 afforded a metallocene-DNA complex which was characterized by 31P NMR spectroscopy. In addition to the resonance for the phosphate backbone (delta-1.6), the spectrum contained 2 signals assigned to a phosphate bound Mo-DNA complex(es) (delta 37.2, 36.5) and a broad signal at delta 6.2 ppm. This result suggests that covalent attachment of the metallocene Cp2MoCl2 occurs via phosphate(O) coordination and is accompanied by local distortion of the DNA backbone. This result supports recent ICP studies with Cp2TiCl2 that have DNA detected DNA-metallocene adducts.

Common elbow injuries in sport.

Athletes of all ages and skill levels are increasingly participating in sports involving overhead arm motions, making elbow injuries more common. Among these injuries is lateral epicondylitis, which occurs in over 50% of athletes using overhead arm motions. Lateral epicondylitis is characterised by pain in the area where the common extensor muscles meet the lateral humeral epicondyle. The onset of this pathological condition begins with the excessive use of the wrist extensor musculature. Repetitive microtraumatic injury can lead to mucinoid degeneration of the extensor origin and subsequent failure of the tendon. Lateral epicondylitis can almost always be treated nonoperatively with activity modification and specific exercises. If the athlete fails to respond to nonoperative treatment after 6 months to 1 year, they are candidates for surgical intervention. Medial epicondylitis is characterised by pain and tenderness at the flexor-pronator tendinous origin with pathology commonly being located at the interface between the pronator teres and flexor carpi radialis origin. Golfers and tennis players often develop this condition because of the repetitive valgus stress placed on the medial elbow soft tissues. Careful evaluation is important to differentiate medial epicondylitis from other causes of medial elbow pain. As with lateral epicondylitis, patients with medial epicondylitis not responding to an extensive nonoperative programme are candidates for surgical intervention. A less common cause of medial elbow pain is medial ulnar collateral ligament injury. Repetitive valgus stress placed on the joint can lead to microtraumatic injury and valgus instability. When the medial ulnar collateral ligament is disrupted, abnormal stress is placed on the articular surfaces that can lead to degenerative changes with osteophyte formation. As with other elbow injuries, a strict rehabilitation regimen is first employed; ligament reconstruction is only recommended if the injury fails to improve and only in athletes requiring a high level of performance. Excessive valgus stress can also lead to posteromedial olecranon impingement on the olecranon fossa producing pain, osteophyte and loose body formation. Arthroscopic elbow debridement can often be helpful in improving motion and in reducing pain in such patients.

Biomechanical evaluation of the medial collateral ligament of the elbow.

UNLABELLED: Anatomical dissection and biomechanical testing were used to study twenty-eight cadaveric elbows in order to determine the role of the medial collateral ligament under valgus loading. The medial collateral ligament was composed of anterior, posterior, and occasionally transverse bundles. The anterior bundle was, in turn, composed of anterior and posterior bands that tightened in reciprocal fashion as the elbow was flexed and extended. Sequential cutting of the ligament was performed while rotation caused by valgus torque was measured. The anterior band of the anterior bundle was the primary restraint to valgus rotation at 30, 60, and 90 degrees of flexion and was a co-primary restraint at 120 degrees of flexion. The posterior band of the anterior bundle was a co-primary restraint at 120 degrees of flexion and a secondary restraint at 30 and 90 degrees of flexion. The posterior bundle was a secondary restraint at 30 degrees only. The reciprocal anterior and posterior bands have distinct biomechanical roles and theoretically may be injured separately. The anterior band was more vulnerable to valgus overload when the elbow was extended, whereas the posterior band was more vulnerable when the elbow was flexed. The posterior bundle was not vulnerable to valgus overload unless the anterior bundle was completely disrupted. The intact elbows rotated a mean of 3.6 degrees between the neutral position and the two-newton-meter valgus torque position. Cutting of the entire anterior bundle caused an additional 3.2 degrees of rotation at 90 degrees of flexion, where the effect was greatest. CLINICAL RELEVANCE: Physical findings in a patient who has an injury of the anterior bundle may be subtle, and an examination should be performed with the elbow in 90 degrees of flexion for greatest sensitivity. As the anterior bundle is the major restraint to valgus rotation, reconstructive procedures should focus on anatomical reproduction of that structure. Parallel limbs of tendon graft placed from the inferior aspect of the medial epicondyle to the area of the sublimis tubercle will simulate the reciprocal bands of the anterior bundle. Temporary immobilization with the elbow in flexion may relax the critically important anterior band of the reconstruction during healing.

Arthroscopic suture repair of superior labral detachment lesions of the shoulder.

Twenty consecutive patients with superior labral anterior and posterior lesions of the shoulder involving the biceps attachment to the labrum (Snyder types II and IV) were repaired arthroscopically and reviewed post-operatively to evaluate the efficacy of the technique in the management of this recently described injury pattern. Follow-up time averaged 21 months (range, 12 to 42). All patients were managed by an arthroscopic repair technique that included debridement of the frayed labrum and abrasion of the superior glenoid neck, followed by the placement of multiple sutures into the torn labrum-biceps tendon complex using a Caspari suture punch. Patients were reexamined, and the results were quantitated with the shoulder evaluation form of the American Shoulder and Elbow Surgeons and with the Rowe rating scale. On evaluation, all patients obtained good or excellent results. This suture technique is recommended in the management of unstable superior labral detachment lesions of the shoulder.

Evaluation of the arthroscopic valgus instability test of the elbow.

Seven fresh-frozen cadaveric elbows were used to evaluate the extent to which the medial collateral ligament must be injured before arthroscopic evidence of valgus instability is seen, the amount of ulnohumeral joint opening that does occur after such an injury, and the elbow position that maximizes visualization of this opening. While visualizing the most medial aspect of the ulnohumeral joint arthroscopically through the anterolateral portal, we sequentially sectioned the medial collateral ligament complex until all of the medial ligamentous restraints were cut. A valgus load was applied after each incision, and the extent to which the ulnohumeral joint opened was measured. Ulnohumeral joint opening was not visualized in any specimen until complete sectioning of the anterior bundle was performed. After the anterior bundle was released, 1 or 2 mm of joint opening was present in all specimens. Complete release of the medial collateral ligament led to dramatic increases in medial joint opening in all seven specimens (4 to 10 mm). Varying the angle of elbow flexion from 15 degrees to 120 degrees revealed that visualization of the medial joint opening was best at 60 degrees to 75 degrees. Finally, forearm pronation increased ulnohumeral joint opening and supination decreased joint opening in all specimens. We found that the entire anterior bundle must be sectioned before measurable and reproducible medial joint opening can occur.

Arthroscopic assessment of the medial collateral ligament complex of the elbow.

The extent that the medial collateral ligament complex could be visualized by arthroscopy was determined in 10 fresh cadaveric elbows from 10 individuals. We carefully exposed the medial collateral ligament complex through a muscle-splitting incision before performing arthroscopy. The anterior and posterior bundles were identified and marked by placing 4.0 nylon sutures deep to the bundles to aid in arthroscopic visualization. A portion of the anterior bundle was visible in only one elbow and in that elbow only the most anterior 25% of the anterior bundle was seen. Attempts to visualize the anterior bundle through additional portals were unsuccessful. Varying the flexion angle of the cadaveric elbow from 0 degrees to 130 degrees also failed to improve visualization. Conversely, the entire posterior bundle, including humeral and ulnar insertion sites, could be seen in all 10 specimens using the posterior portals. We also noted that direct pressure was placed on the ulnar nerve in all specimens when the arthroscope or any arthroscopic instrument was advanced into the posteromedial gutter in contact with the posterior bundle because of its proximity immediately adjacent to the ulnar nerve. The inability to reliably see the anterior bundle and the humeral or ulnar insertion sites of this ligament may limit the value of the arthroscope when assessing medial collateral ligament injuries. Additionally, great care should be taken when using the arthroscope or other instruments in the posteromedial gutter because the ulnar nerve lies immediately adjacent to the thin posterior bundle and capsule.

Isolated closure of rotator interval defects for shoulder instability.

Fifteen patients noted at surgery to have an isolated defect in the rotator interval and no other pathologic abnormality underwent closure of the defect as an isolated procedure for recurrent instability symptoms. Intraoperative assessment of each of these shoulders after the closure demonstrated adequate stability, and no other stabilization procedures were performed. The average age of the patients was 24 years, and 10 of the 15 patients were women. Examination under anesthesia revealed increased inferior translation in all patients, as illustrated by at least a 1+ sulcus sign. The rotator interval defect averaged 2.75 cm in width and 2.3 cm in height. The rotator interval defect edges were freshened and approximated (nine patients) or imbricated (six patients), depending on the anterior capsular laxity and the degree of glenohumeral joint translation possible. Followup averaged 3.3 years (range, 2.2 to 5.3), and all patients achieved either a good or excellent result using the American Shoulder and Elbow Surgeons evaluation scale and the Rowe rating scale. Although most patients with a defect in the rotator interval require a standard stabilization procedure as a supplement to closure of the defect, approximation or imbrication of the defect as an initial step at surgery may confer adequate stability in selected patients and obviate the need for formal capsular advancement.

Anterior superior instability with rotator cuff tearing: SLAC lesion.

Anterosuperior instability of the shoulder may occur from a variety of pathologic lesions. We describe a specific entity, the SLAC (superior labrum, anterior cuff) lesion that involves an association of anterior-superior labral tear with a partial supraspinatus tear. We retrospectively isolated a group of 40 patients with this lesion. The presenting complaints, physical examination findings, surgical findings, and results were isolated. Overhead activities were the most common etiology; load and shift instability testing and whipple rotator cuff testing were the most common physical examination findings. Surgical repair was successful in 37 of the 40 patients. The SLAC lesion is a definable clinical entity with predictable history, examination, surgical pathology, and satisfactory results from surgery.

Massive rotator cuff tears: debridement versus repair.

In many studies, short-term and midterm results of debridement seem to show satisfactory results. However, the three long-term studies currently available all report that these initial results deteriorate significantly with time and are not acceptable. If debridement is considered, careful preoperative and intraoperative evaluation as discussed by Burkhart should be followed. We believe an adequate understanding of the anatomic subtleties, pathologic changes, biomechanical forces, and advanced reconstructive techniques allows repair to be performed in most, if not all, rotator cuff tears of the shoulder. The findings of the study described herein indicate that repair of these tears is the treatment of choice.

Elbow arthroscopy in trauma and reconstruction.

Arthroscopy of the elbow has become a valuable adjunct in the evaluation and treatment of elbow trauma and reconstruction. Arthroscopic visualization aids diagnosis and treatment while minimizing surgical trauma. The indications and techniques of elbow arthroscopy continue to expand and evolve. This article demonstrates the use of elbow arthroscopy as it relates to some of the topics in this volume. Arthroscopic setup, portal anatomy, technique, as well as an overview of trauma, loose bodies, bursitis, instability, arthrofibrosis, arthritis, and complications are discussed.

Arthroscopic repair of partial-thickness tears of the rotator cuff.

Management of partial-thickness tears of the rotator cuff should include consideration of tear size, tear depth, patient age and activity level, and tear etiology. We present an arthroscopic technique for repair of articular surface partial-thickness tears that may promote healing by closing the tendon side-to-side, placing the debrided tendon end in contact with an abraded humeral surface. By repairing selected partial-thickness tears, progression of the tear and the need for subsequent repair may be prevented. Our preliminary results in 28 patients are encouraging and suggest that this technique is a useful adjunct to tendon debridement for articular surface partial-thickness tears of the rotator cuff.

Laser-assisted capsulorrhaphy for multidirectional instability of the shoulder.

PURPOSE: The purpose of this study was to review the clinical results of laser-assisted capsulorrhaphy performed on 27 shoulders in 26 patients for multidirectional shoulder instability with minimum follow-up of 2 years. TYPE OF STUDY: Prospective case series. METHODS: Laser shrinkage was performed on the entire capsule. In patients in whom the rotator interval did not shrink, suture plication of this area was performed. All patients were evaluated with respect to the incidence of recurrent instability, need for reoperation, and ability to return to their previous level of activity or sports participation. In addition, all patients were rated as satisfactory or unsatisfactory using criteria established by Neer. RESULTS: Twenty-six of 27 shoulders (96%) remained stable and asymptomatic a minimum of 2 years after surgery. Of 14 athletes in the study group, 12 (86%) returned to their previous level of sports participation. CONCLUSION: Our results suggest that laser-assisted capsulorrhaphy is an effective treatment alternative for multidirectional instability.

Basics of elbow arthroscopy.

With more innovation in arthroscopic equipment and surgical technique, elbow arthroscopy will continue to evolve and new indications will emerge. Strict adherence to the principles outlined above will allow the use of arthroscopy to treat a variety of elbow disorders in a safe and effective manner.

Osteochondritis dissecans of the elbow.

Osteochondritis dissecans of the elbow remains one of the leading causes of permanent elbow disability in adolescents and young adults engaged in throwing sports or gymnastics. The insidious onset of lateral elbow pain and restriction of full extension should alert the physician and prompt further investigation. Early recognition and appropriate treatment may allow for the prevention of long-term sequelae. Conservative care following early detection provides the best opportunity for a complete recovery. Surgical management at this point consists primarily of excision or removal of the osteochondral fragment with drilling or burring of the base of the lesion. Prognosis is fair with approximately half of all patients experiencing chronic pain or limitation of motion in the elbow. Research efforts are currently focusing on the treatment of established articular surface defects. Newer procedures such as the transplantation of osteochondral, perichondral, and periosteal tissues, chondrocyte transplantation, and the biochemical manipulation of the chondrocyte environment may provide us with exciting new approaches to an old problem. Osteochondritis dissecans of the elbow continues to present a difficult challenge to the treating physician. The current literature provides very little guidance for the clinician but active and innovative investigations into the treatment of articular cartilage defects may soon provide the answers.

Arthrofibrosis and complications in arthroscopy of the elbow.

The authors offer concise procedural advice for arthroscopic treatment of flexion contractures of the elbow, bracketed by indications for treatment and recommendations regarding postoperative complications.

Thermal versus suture treatment of symptomatic capsular laxity.

This article reviews the clinical results of unipolar thermal capsular shrinkage in 30 patients and compares that group to similar groups previously managed by laser-assisted capsulorrhaphy or by an arthroscopic capsular shift procedure. Patients were evaluated with respect to incidence of recurrent instability, the need for reoperation, and the ability to return to previous levels of activity or sports participation. Patients were rated as satisfactory or unsatisfactory based on criteria established by Neer. The results of this study suggest that thermal capsulorrhaphy with rotator interval plication is an effective treatment alternative for multidirectional instability, with results comparable to those previously reported with open and arthroscopic procedures.

Elbow injuries.

Injuries about the elbow are common in racquet sports. Lateral epicondylitis is seen most often, but symptoms can arise from other sources including the medial elbow and the articular surfaces themselves. Medial elbow symptoms can result from medial epicondylitis, medial collateral ligament injury, ulnar nerve trauma, or any combination of these injuries. Careful evaluation of medial elbow pain is required to define the causes. Proper technique, conditioning, and equipment are also important in reducing the risk of injury to the elbow.

Osteochondritis dissecans of the elbow.

Osteochondritis dissecans of the elbow remains a difficult problem to manage in the young athlete. Though the etiology is unclear, a definite association between overuse with repetitive microtraumatic insult and OCD has been established. Early detection and appropriate treatment can provide the best chance for preventing an unfavorable outcome. In many cases, conservative treatment regimens will provide complete resolution of symptoms, return of function, and full recovery, including return to sports participation. Surgical indications should be recognized, however, and surgical management carried out when warranted. Most authors treat unstable lesions primarily by excision of the fragment, accompanied by drilling or burring of the base of the lesion. Symptoms usually improve significantly, but approximately half of all patients will continue to experience chronic pain or limitation of elbow motion, highlighting the significance and severity of OCD of the elbow.

Arthroscopic capsulodesis of the lunotriquetral joint.

A case series consisting of 20 consecutive patients with persistent ulnar-sided mechanical wrist pain, lunotriquetral interosseous (LTIOL) ligament tears resulting in joint incongruity and increased laxity, and traumatic triangular fibrocartilage complex (TFCC) tears was reviewed. Each patient underwent an arthroscopic reduction and internal fixation (ARIF) of the lunotriquetral joint, arthroscopic disk-carpal (disklunate-ulnocapitate-disktriquetral, DL-UC-DT) ligament plication, and TFCC repair or débridement. There were 12 right wrists and 8 left wrists, of which 12 were dominant. The mean patient age was 33 years; 7 patients had workers' compensation claims and 2 had legal claims. Fourteen patients recalled a specific injury mechanism, such as hyperextension or rotation. The accompanying traumatic TFCC tears were peripheral in 15 and linear radial in 6 patients (one patient had concomitant peripheral and radial linear tears), and in 6 cases, the palmar ulnocarpal extrinsic ligaments were partially torn. The mean preoperative modified Mayo Wrist Score was 50, and at a mean of 3.1 years after surgery, the score had increased to 88. There were 13 excellent, 5 good, and 2 fair results. Four patients had complications, including transient tenderness along the extensor carpi ulnaris and persistent neuritis of a dorsal branch of the ulnar nerve. Overall wrist comfort and function, as indicated by the modified Mayo Wrist Scores, improved after arthroscopic stabilization of ulnar-sided wrist injuries (pinning of the lunotriquetral joint, disk-carpal ligament plication, and TFCC repair or débridement).

Posterolateral rotatory instability of the elbow.

Since its original description by O'Driscoll in 1991, PLRI is becoming increasingly recognized as a significant cause of elbow pathology. It is well documented that this problem results from an insufficiency of the radial ulnohumeral ligament and its related lateral structures, and that this insufficiency is usually the result of elbow trauma. Diagnosis has improved with the introduction of the PLRI test to identify the instability and advancing MR imaging capabilities of illustrating the injury. Whereas open reconstruction was previously the only definitive treatment, improving arthroscopic techniques provide a satisfactory alternative in stabilizing the elbow.