ABSTRACTS 163

ethylene chlorhydrin) were implicated as the cause of many of the failures. The purpose of this paper was to examine the biochemical effects of FD- ETO-BPTB wear debris on synoviocytes by mea- suring IL- 1 production.

The FD-ETO-BPTB allografts were purchased from the Utah Lions Eye and Tissue Bank (Salt Lake City, UT, U.S.A.). Each ligament was recon- stituted according to the guidelines supplied by the tissue bank. Each ligament was then minced under antiseptic conditions and then ground in a freezer mill under liquid nitrogen. The sizes of the resultant wear particles were measured using a computer- aided image analyzer with visualization limits to 1 pm. A line of lapine synovial cells (HIG-82) previ- ously established in our laboratory through the spontaneous transformation from an aging primary culture were grown to confluent monolayers in 4-ml culture flasks. The HIG-82 cell line has retained the differentiated biochemical properties of the primary synoviocytes from which it was derived. Once grown to confluence, a final wear particle concen- tration of 1 mg/ml was added directly to the mono- layer surface. To insure intimate contact between the particles and the cells, the cultures underwent a 4-h “dryout” period prior to addition of serumless Neuman-Tytell medium. After 72 h of incubation, the particle-conditioned medium was recovered and assayed for IL-1 using a lymphocyte proliferation assay that measures the uptake of tritiated thymi- dine by DlOG4.1 cells. The IL-l levels were com- pared with negative control (no wear particles) and positive control (phorbol myristate acetate [PMA] O.l-&ml flasks).

Wear particle size, as determined by image anal- ysis, correlated well with the size of particles re- covered from human synovial biopsies. Most parti- cles fell within a size distribution of 2-30 pm.

Table 1 contains the means and standard devia- tions for the FD-ETO-BPTB particle conditioned media, positive control media, and negative control media. The student’s t-test was used to compare results. When compared to the negative control, the FD-ETO-BPTB particle conditioned media induced a statistically significant (p < 0.01) elevation in IL-l production.

IL-1 has many biochemical actions. In vitro, IL-l induces synoviocytes and chondrocytes to produce PGE2, collagenase, and phospholipase A2. Also, IL-l causes chondrocytes to decrease their matrix synthesis. In addition, IL-l can induce its own syn- thesis in an autocrine fashion. As a result, IL-l is a

potent mediator of connective tissue destruction and inflammation and can be found in the synovial fluid of individuals with inflammatory arthritis as well as osteoarthritis.

Wear particles generated from FD-ETO-BPTB allografts induced statistically significant levels of IL-l. The IL-l production due to FD-ETO-BPTB allograft wear particles may play a role in tissue inflammation and destruction post-ACL replace- ment.

TABLE 1 IL-l production by synoviocytes (U/ml)

Negative control 0.137 f 0.088 FD-ETO-BPTB 0.824 f 0.373 Positive [PMA] 22.5 f 2.90

A Prospective Evaluation Comparing Arthroscopic and Open Treatment in the Management of Recurrent Anterior Glenohumeral Dislocation. Stephen C. We- ber. Sacramento, California, U.S.A.

This study prospectively evaluates the treatment of anterior glenohumeral instability using both ar- throscopic and open techniques by a single surgeon. Patients were randomly assigned to either treatment based on their preference after a discussion based on previously published rates of recurrence and op- erative morbidity for these techniques. Twenty- three patients selected arthroscopic treatment and 21 open repair. Arthroscopic suturing or fascia lata graft repairs were done for all arthroscopic repairs as described by Caspari; an open Bankart technique was performed as described by Rowe. Both groups were managed with sling’ immobilization for 3 weeks and pendulum exercises for an additional 3 weeks. Follow-up time averaged 32.6 months for arthroscopic and 23.8 months for open treatment. One superficial infection and one temporary neuro- praxia occurred in the arthroscopic group; none oc- curred in the open group. Hospital stays averaged 1.1 and 3.2 days, respectively. Arthroscopic repairs were managed with oral narcotics; open repairs rou- tinely required parenteral narcotics for 24-48 h. Ar- throscopic repairs were uniformly pain free at 3 months; only 20% of open repairs were. There were no recurrences in the open group. Four patients had redislocations in the arthroscppic group, three with suture repairs. Three of the recurrences were in contact athletes or patients not compliant with post- operative immobilization. All were treated success- fully with open repair, not felt to be complicated by their prior surgery. At follow-up observation, ar-

Arthroscopy, Vol. 6, No. 2, 1990

ABSTRACTS

throscopic repairs had full recovery of motion; open repairs lacked an average of 9” external rotation. Both techniques offer good results. Arthroscopic techniques seem best suited to patients who require full external rotation or prefer a less painful proce- dure; open repair is best suited for those patients where recurrence is less acceptable. Contact ath- letes and patients not willing to comply with immo- bilization are not suitable for arthroscopic repair.

Innervation of the Human Knee Joint by Substance P Fibers. Edward M. Wojtys, Douglas Beaman, Roy A. Glover, and David Janda. Ann Arbor, Michigan, U.S.A.

Anterior knee pain is a frequent musculoskeletal complaint affecting all ages, both sexes, and ath- letes and nonathletes alike. Numerous theories have been proposed regarding its etiology, includ- ing patellar malalignment , quadriceps insufficiency, patelIar subluxation, quadriceps muscle tightness, and chondral defects. However, the mechanism by which these factors produce this pain is not clear. To better understand painful syndromes about the knee, the authors investigated the presence of no- ciceptive nerve fibers in 11 human knee specimens, eight from patients with degenerative patellofemor- al disease and three from normal subjects. Immu- nohistochemical techniques using monoclonal anti- body to substance P were employed. (Substance P is a neurotransmitter known to be important in sen- sory nerve fibers responsible for pain transmission. It is also a powerful inflammatory agent capable of producing vasodilatation and joint effusion.) Sub- stance P fibers were isolated in the retinaculum, fat pad, periosteum, and subchondral plate of patellae affected with degenerative disease. In the degener- ative specimens, substance P fibers could be seen at the bone hyaline cartilage interface; however, these fibers were not present at the hyaline cartilage sub- chondral plate interface of normal specimens.

This study demonstrates that selective tracing of nociceptive pain fibers is possible around the knee in both soft tissue and, in some circumstances, bone. There is some evidence that the pattern of innervation changes with degenerative disease. We also postulate that certain orthopedic procedures such as lateral retinacular release and fat pad resec- tion may be denervating procedures, possibly pro-

ducing their beneficial effects by decreasing the concentration of substance P released into affected knee joints.

Anatomy and Diagnostic Arthroscopy of the Sub- acromial Bursa. Eugene M. Wolf. San Francisco, California, U.S.A.

The objective was to study the gross and arthro- scopic anatomy of the subacromial space. An ana- tomical and a clinical study of the subacromial bursa was undertaken to provide orientation and guidelines in diagnostic arthroscopy of the subacro- mial space. This study attempts to clarify some con- cepts that have developed through our early expe- rience in this area.

The subacromial bursae and glenohumeral joints of 15 fresh cadaver shoulder specimens were exam- ined arthroscopically. Lateral, posterior, and ante- rior arthroscopic portals were used to examine the extent of the bursa. AlI intrabursal structures and their relationships were identified. The arthroscopy was then followed by a detailed anatomical dissec- tion. In the clinical study, 23 patients underwent arthroscopy of the subacromial bursa and gleno- humeral joint, for diagnosis and treatment of im- pingement .

A technique of diagnostic bursoscopy was devel- oped to consistently enter the bursa and observe its contents without using a motorized shaver. The lim- its and contents of the space and the medial, lateral, and anterior sulci were defined. The rotator cuff, the coracoacromial ligament, the subdeltoid fascia, and the inferior surface of the acromion were uni- formly identified and pathologic findings were noted.

This study defines the anatomy of the subacro- mial space and demonstrates that diagnostic sub- acromial bursoscopy, used in conjunction with gle- nohumeral arthroscopy, is an important adjunct in the diagnosis and treatment of impingement. This technique consistently permits a traumatic entry into the subacromial space and the demonstration of intrabursal impingement lesions prior to the use of a motorized shaver. These subacromial lesions can be the only lesions present in impingement syn- dromes and should be identified prior to proceeding with a subacromial decompression.

Arthroscopy, Vol. 6, No. 2, 1990