Knee arthrofibrosis: prevention and management of a potentially devastating condition.

Knee arthrofibrosis, which usually occurs after trauma or surgery, can inhibit joint biomechanics. An elaborate interaction of growth factors and other inflammatory mediators initiates and coordinates this deleterious tissue proliferation. Knowledge of risk factors can aid clinicians in helping patients avoid knee arthrofibrosis. Once the condition is present, a history and examination are imperative to institute the most appropriate treatment regimen. Nonoperative measures can be used as therapy, though surgery is often necessary for optimal results.

Biceps tendon disorders in athletes.

It has been proposed that the long head of the biceps functions as a humeral head depressor and stabilizer. In addition, in many overhead sports, the biceps helps to accelerate and decelerate the arm. With improper training or fatigue, inordinate stresses can be placed on the biceps as it attempts to compensate for other muscles. This can lead to attrition and failure, either within the tendon substance or at its origin. Bicipital problems in athletes usually occur in conjunction with other types of shoulder disorders, such as rotator cuff impingement and glenohumeral instability, making determination of the role and degree of biceps involvement difficult. Conditions affecting the biceps tendon in athletes can be generally classified as degeneration, instability, and disorders of the origin. Because of the close association of biceps lesions with other abnormalities, a thorough evaluation of the shoulder with a suspected biceps disorder is essential. Treatment of bicipital problems in athletes must often be accompanied by treatment of associated shoulder conditions.

The relationship of the axillary nerve to arthroscopically placed capsulolabral sutures. An anatomic study.

Ten cadaveric shoulders (mean donor age, 60.5 years) underwent arthroscopic placement of capsulolabral sutures as performed during arthroscopic reconstruction for shoulder instability. In relation to the glenoid face, the sutures were placed anterior, anteroinferior, inferior, posteroinferior, and posterior. All sutures entered the capsule approximately 1 cm away from the glenoid and exited beneath the labrum, and were tied using arthroscopic knot-typing techniques. The shoulders were frozen in the lateral arthroscopic position of approximately 45 degrees of abduction and 20 degrees of flexion and sectioned in the plane of the glenohumeral joint. The axillary nerve was then dissected, and the average distance from the nerve to each suture was found to be 16.7 mm at the anterior position, 12.5 mm at the anteroinferior position, 14.4 mm at the inferior position, 24.1 mm at the posteroinferior position, and 32.3 mm at the posterior position. In no specimen was any suture closer to the axillary nerve than 7 mm. We noted a statistically significant trend for the nerve to lie closest to the anteroinferior suture and gradually recede from the remaining sutures lying more posteriorly. This anatomic study is the first to demonstrate a relatively safe margin for arthroscopic suture placement between the capsule and axillary nerve when these sutures are placed approximately 1 cm from the glenoid rim.

Arthroscopic capsular plication for posterior shoulder instability.

Seventeen patients with recurrent posterior shoulder instability underwent posterior capsular plication with or without suture anchors, between 1990 and 1992. Minimum 2-year follow-up was available for 14 patients (average, 33 months; range, 24 to 45 months). The etiology involved trauma in 9 cases, recurrent microtrauma in 4 cases, and no trauma in 1 case. Posterior capsular laxity was present in all 14 cases and was believed to be the primary pathology, although 12 patients showed some form of labral pathology. The patients were interviewed and assessed in six categories: pain, strength, function, stability, range-of-motion, and satisfaction. Twelve patients had excellent results and 2 had fair results. Nine of 10 patients who participate in recreational or competitive athletics reported full return to their preinjury level of function in their respective sports. There was one recurrence of posterior shoulder instability which was remedied with a second arthroscopic posterior capsular reconstruction. All 14 patients were satisfied with the results of their surgery, and no complications were noted. Capsular plication is a promising technique in the treatment of recurrent posterior shoulder instability.

Arthrometric evaluation of posterior cruciate ligament injuries.

We reviewed the clinical examinations and knee arthrometry evaluations of 40 patients: 10 with posterior cruciate ligament injuries, 10 with combination anterior and posterior cruciate ligament injuries, 10 with anterior cruciate ligament injuries alone, and 10 with no history of knee injury. Using a 3-mm side-to-side difference as the minimal limit for detection of posterior cruciate ligament injury, the sensitivity of the arthrometer at 40 pounds of posterior force was 90%, the specificity was 100%, the predictive value of a positive test was 100%, and the predictive value of a negative test was 91%. When total anterior-posterior translation was assessed, the sensitivity was 100%, the specificity was 85%, the predictive value of a positive test was 87%, and the predictive value of a negative test was 100%. The overall accuracy of arthrometry for detection of posterior cruciate ligament injury was 96% for 40 pounds of posterior force and 94% for total anterior-posterior translation at 40 pounds. Grade 1 posterior cruciate ligament injuries had significantly greater arthrometric posterior translation compared with grade 0 (normal) knees. Regression analysis showed arthrometric laxity measurements correlated well with the clinical grade of the posterior drawer test. Finally, the accuracy of the arthrometer was not affected by concomitant anterior cruciate ligament injury.

Medial compartment arthrosis of the knee.

When the resultant forces on the tibial plateau are displaced medially, compressive stresses cause apposition of bony tissue, thus thickening the dense subchondral bone underlying the medial plateau. Loss of the articular cartilage and an increase in subchondral bone density facilitate the progression of osteoarthrosis. Surgical management is dependent on the presence of a varus deformity; patients with medial compartment disease and varus alignment should be considered for high tibial osteotomy (HTO) or unicondylar or total knee arthroplasty (TKA), depending on their age and activity level. Patients without varus deformity and with mechanical symptoms, only mild joint-space narrowing, and pain less than 1 year are likely to benefit from arthroscopic débridement. Patients without varus alignment but with chronic pain associated with loading and more pronounced joint-space loss should be considered for HTO, or unicondylar or TKA.

Lower-limb proprioception in above-knee amputees.

A proprioception measurement system was designed and constructed to evaluate lower-limb knee joint proprioception in ten above-knee amputees. The system permitted the testing of subjects in a position simulating late swing phase of gait. The threshold for detection of slow passive motion and the ability to reproduce specified lower-limb positions were recorded for the sound and the prosthetic limbs of the subjects. A significant difference was detected between prosthetic and sound limb passive motion detection threshold; however, no difference was found between prosthetic and sound limb passive motion reproduction. This finding suggests the importance of hip joint motion appreciation in the amputees' proprioception of the prosthetic knee joint when these motions are associated. Prosthetic limb passive motion reproduction error decreased with age, suggesting that the amputees may improve their ability to use remaining lower limb proprioceptive mechanisms to compensate for the loss of anatomic knee joint structures.