Citations

The stabilizing capacity of the ligaments and articular surface in the ankle was determined under defined physiologic loading conditions. The concept of primary and secondary constraints was adapted to the ankle. With physiologic loading, the articular surface ac counted for 30% and 100% of stability in rotation and version, respectively. That the articular surface was the sole source of inversion and eversion stability under the prescribed physiologic loading conditions has not been previously reported. The demonstration that the articular surface resists inversion displacement in the loaded ankle supports the conclusion of previous studies that rotation, rather than inversion, may account for a type of clinically sympto matic ankle instability. Further, ankle instability may occur during loading and unloading but not once the ankle is fully loaded. The results of our study confirm the importance of the anterior talofibular and calcaneo fibular ligaments and suggest an important role for the deltoid ligament.

We studied the results of treatment in 110 of 129 consecutive patients who had knee instability for which they underwent reconstruction of the knee ligaments at the Mayo Clinic. Thirty-one patients underwent dif ferent types of extraarticular reconstruction. Nine (29%) had recurrence of the knee giving way, and 11 (36%) had objective signs of instability on examination. Fifty- five patients underwent combined extraarticular and intraarticular reconstruction with either the Lam-Jones patellar tendon (PT) procedure (21 knees) or the Zarins- Rowe semitendinosus and iliotibial band (ST & ITB) procedure (34 knees). Only two knees (10%) with PT procedures and three knees (9%) with ST & ITB pro cedures continued to have giving way. Three patients in each group had recurrence of instability. Twenty-four knees with acute instability had either primary repair (17 knees) or primary reconstruction with ST & ITB procedures (7 knees). The results in these knees were superior to the results in the knees reconstructed for chronic instability. On the basis of our 2 year results, we believe that a combined intraarticular and extraar ticular reconstruction is the procedure of choice in chronic knee instability and is a useful procedure in acute knee instability with irreparable tears of the an terior cruciate ligament.

All patients treated for a first-time anterior glenohumeral dislocation in Olmsted County, Minnesota, from 1970 through 1979 were identified. Of these 124 patients, 116 were available for study at a mean followup of 4.63 years (range 2 to 11). Of the 116 patients, 38 (33%) had recurrence of dislocation: 21 of the 32 (66%) pa tients less than 20 years old,17 of the 43 (40%) patients 20 through 40 years old, and none of the 41 patients older than 40 years. Symptomatic instability remained a problem in 24 patients. Twenty-seven of 33 (82%) young athletes had recurrence of dislocation as com pared with only 8 of 27 (30%) nonathletes of similar ages. Patients restricted from resuming sports partici pation for 6 weeks or more had significantly better results than those restricted for less than 6 weeks. The recurrence rate of dislocation is not as high as previously reported. However, the rate in athletes is much higher than that in nonathletes. Many patients continue to complain of symptomatic instability without actual redislocation. In our younger patients, we now advise immobilization for from 3 to 6 weeks, followed by extensive rehabilitation before return to athletic ac tivity.

This preliminary study of four elbow specimens inves tigates the relationship of articular geometry and liga mentous structures in providing stability to the elbow joint. A technique is presented that describes the con straining features of varus-valgus and distraction in extension and at 90° of elbow flexion. Valgus stability is equally divided among the medial collateral ligament, anterior capsule, and bony articulation in full extension; whereas, at 90° of flexion the contribution of the ante rior capsule is assumed by the medial collateral ligament which provides approximately 55% of the stabilizing contribution to valgus stress. Varus stress is noted to be resisted primarily by the anterior capsule (32%) and the joint articulation (55%) with only a small (14%) contribution from the radial collateral ligament. At 90° of flexion, little change is noted in the contribution to the radial collateral ligament (9%), but the anterior capsule offers only 13%, with the remaining stability (75%) arising from the joint articulation. In extension, the soft tissue resistance to distraction is provided minimally by either the radial (5%) or the medial (5%) collateral ligaments, and thus primarily originates from the anterior capsule (85%). At 90° of flexion, however, the capsule offers virtually no resistance to distraction (8%). The radial collateral ligament contributes 10% of the stability, while the medial collateral ligament ac counts for 78% of the resistance to distraction in this position. Too few specimens have been studied to form any conclusions for direct clinical applications at this time. However, the technique provides a reliable tool with additional studies for different positions and loading conditions underway. These efforts should disclose useful information that might be applied to the manage ment of chronic elbow instability, radial head or olecra non fracture, the design and implantation of elbow prostheses, or provide a rationale for other reconstruc tive procedures.

The practice of prophylactic ankle taping or wrapping to reduce the incidence of inversion ankle sprains in athletes has come under attack. The purpose of this study was to measure objec tively one ankle taping technique's ability to withstand the stresses placed upon it by a standardized exercise routine. Electrogoniometers were used to measure the three-dimen sional ankle motion of 20 subjects walking on a level surface and a 10° sideslope. The evaluations were carried out under these three conditions: (1) both ankles untaped, (2) both ankles taped before exercises, and (3) both ankles taped after exercise. The results from this study indicate that the tape does indeed restrict those motions associated with inversion ankle sprain. Methods similar to those described in this study could be used in the evaluation of many current training room practices and thereby provide an objective rationale for their application.

The effect of repeated ball impacts on the handball player's hands was studied by using thermography and routine roent genography to determine evidence of altered perfusion or other tissue changes. Seventeen of 22 players had multiple areas of decreased perfusion, 12 of these 17 were symptomatic and 8 showed definite correlation between symptoms and thermo graphic findings. No skeletal or articular changes were noted. Players with more than 200 hr of accumulated playing time had increased risk of developing symptomatic, although nonpro gressive, alterations in perfusion of their hands but did not have evident skeletal changes.

Ipsilateral headache associated with hypoglossal nerve palsy is uncommon and is usually reported to be secondary to internal carotid artery dissection. Herein, we report three idiopathic cases of berign ipsilateral headache with hypoglossal nerve palsy.