The following contribution to Arthroscopic Advances is the second of a two-part series on arthroscopy of the ankle. Pan one was anatomical features and appeared in the December 1985 issue.
Arthroscopy of the ankle joint was done initially witfi the needlescope or small diameter scope (Watanabe #25) from the anteromedial or anterolateral approach as advocated by Johnson and Ikeuchi (personal communication). Lesions such as the meniscoid of the ankle,1 chondral fragments, status of osteochondritis dissecans and chronic synovitis were evaluated prior to open surgery or other treatment. The meniscoid is a posttraumatic band of fibrosed synovial tissue in the lateral ankle extending from me anterior talofibular ligament to the posterior talofibular ligament. Later when the larger diameter scopes became of practical use in the joint, one could see more clearly. Other portals, such as the central, posteromedial and posterolateral were developed and reported by Drez, Guhl and Gollehon.2-* Surgery via the scope was then demonstrated by Schonholtz (personal communication), Guhl,5-7 and Andrews et al (personal communication), at various arthroscopy courses. Procedures performed and illustrated were: loose body removal, drilling and debridement of osteochondritis dissecans, fracture and other chondral defects, removal of meniscoid or "plica" of the ankle, removal of adhesions and synovial impingement, trimming of osteophytes, removal of radiopaque or radiolucent chondral fragments, as well as synovectomy, for various reasons. Consideration of stabilization procedures and ankle fusion techniques witíi the use of the scope appear to be distinctly possible and advantageous.
To date, 3,500 arthroscopic procedures have been performed by the author from 1974 through 1984, 81 of which were of the ankle, 39 diagnostic and 30 surgical procedures. Twelve more surgical procedures were done in the last eight months with the use of the new techniques which are described in this article.
Originally, restricted visualization of the joint limited the surgeon's ability to evaluate the problem. Surgical procedures were indefinite. Proper positioning of the patient also was a challenge. The drilling and debridement of talar osteochondritis dissecans, treatment of fracture defects and the management of lesions in the posterior compartment on the dome of the talus or tibial plafond was potentially hazardous.
There also appears to be an increasing number of symptomatic lesions of the soft tissue described as the meniscoid, adhesions, local synovitis and the synovial impingement syndrome (Fig. 1, 2, 3, 4). These appear to be responsive to arthroscopic surgery after failure of conservative treatment. It is important to keep in mind that mere are variations in me anatomy and physiology of me ankle joint just as in the knee and other joints. Also, an experienced arthroscopist should be trained to recognize this.
Techniques for easier access were developed by the author. To date, a small series of cases and early laboratory study appear to substantiate and offer a far better approach to solve some of these problems. One can then explore this joint and treat these lesions wiüi far more confidence and safety.
The first is to distract the ankle joint by one of three methods, which appears to be harmless. The second is the development of two new means of approach, the transmalleolar and transfibular portals. The latter is done safely under image and arthroscopic control and serves for the passage of Kirschner wires, drills, curettes, debriders and cutters. These methods are carried a step further for arthroscopic ankle reconstruction or stabilization and arthrodesis.
Fig. I: Symptomatic lesion in the posterior tibial plafond as seen on this tomogram (arrow).
Fig. 2: Band of fibrous tissue adhesion in the anterior ankle joint in a 16 year old boy causing recurring locking, severe pain and repeated disability over several years. This was removed arthroscopically and immediate relief was obtained and remains so at the present time.
Fig. 3: Synovial impingement, symptomatic in mid-portion of talar malleolar joint. (Right, medial malleolus and talus, left).
Fig. 4: Double fibrous band adhesions in the posterior ankle joint. Relief by local excision along with joint debridement and minisynovectomy was obtained.
A small set of ankle instruments for certain uses has been developed. In most cases the instruments for routine use in the knee and shoulder can be employed. The Hennings distractor (Fig. 5) originally designed for meniscus repair in the knee, is employed for medial (valgus), lateral (varus) or direct double distraction of the joint (Fig. 6, 7, 8).
Materials and Methods
To date, ten surgical cases were done employing distraction and two cases for drilling; one, an intact lesion of osteochondritis dissecans and one, a chondral defect of the dome of the talus. There have been no harmful effects noted. The osteochondritis lesion of the talus is healing on x-ray at three months, postoperative (Fig. 9-13). Eleven of the 12 cases are significantly improved.
Fig. 5: Distraction device employed by the author.
A series of below the knee amputation specimens, cut off 6 inches above the ankle and at midfoot have been studied. Although the specimens have been distracted with sufficient force to produce bending of the pins, the ligaments have maintained their strength. This was done in a pre- and post-dissected ankle, where all soft tissue was dissected away leaving only the ligaments and bone. The amount of weight employed attempting to stretch or tear the ligaments , or cause the pin to bend , break or cut out of the os calcus was recorded. As stated, the pins bent first. A review of the literature regarding talar tilt was used to further substantiate the method.
Differential diagnosis of the extra-articular lesions of the ankle, as illustrated by Kelikan, should be considered before proceeding, but need not be described in this preliminary report.8
Each patient in which indications have been established and who is scheduled for an arthroscopic diagnostic or surgical procedure will be prepared and followed in the manner described. Stress ankle x-rays are routinely taken preoperatively and six months postoperatively in varus and valgus stress, as well as again under anesthesia. Pre- and postoperative neurosensory examinations are done. Final evaluation of the end result of the employed technique and the surgical procedure is scheduled at six months and one year. Documentation will be by the history and clinical findings, 35mm slides for outside and arthroscopic views, television tapes, image, x-ray. cineradiographic recordings and specimen biopsies.
The procedures are done under general anesthesia in a standard hospital operating room, or in a free-standing Day Surgery Center. The established position is with the patient supine with the hip and knee flexed and the extremity placed over a large foam rubber triangle. The other choice would be to have the extremity in a leg holder over the end of the table. These both should allow good access to all portals for instrumentation and camera. The ankle is entered with an 18 gauge needle from the anterolateral side and the joint distended before the scope is inserted replacing the needle. Drainage is obtained by a second needle, or by alternating the ingress and egress spigots on the scope. Ankles with long standing chronic pathology often must be debrided with a shaver, cutter or trimmer before the above technique can adequately be employed. Repeat distension also stretches the capsule allowing more room.
Fig. 6: X-ray showing device for lateral varus distraction of the ankle joint.
There are five standard portals through which the ankle joint may be observed. Anteriorly it may be seen through an anterolateral, an anteromedial or an anterocentral approach. Posteriorly the two routes are posteromedial or posterolateral.
Anterolaterally the ankle is entered between the fibula and talus. The common extensor tendons are just medial to the incision. The anterocentral portal is situated between the extensor digitorum communis and the extensor hallucis longus. Anteromedial Iy the ankle is entered between the medial malIeolus and talar dome. The portal lies medial to the previously mentioned structures. The two posterior approaches are adjacent to the medial and lateral borders of the Achilles tendon and are also slightly below the joint line. Diagrams (Fig. 14, 15) indicate the anatomical structures to be avoided.
Fig. 7: X-ray showing distraction of the joint with two abstractors, medial and lateral.
The trans-malleolar portals mentioned are started with a Kirschner wire of 2 cm to 3 cm above me joint line and pass through the bony structures down to the outer edge of talar dome on each side. These are developed under arthroscopic and fluoroscopic control. It is helpful to mark die joint line and some of the important anatomical structures on the skin at the beginning of the procedure. Accessory portals, ie, to the anterolateral or to me anteromedial and others, can be used for triangulation in doing surgery. Most portals are developed by hypodermic needle to check for position.
A 4.76 mm threaded Steinman pin is inserted into the distal tibia and os calcus on the medial side for valgus stress and into the tibia or fibula on the lateral side for varus stress. Gradual and careful distraction is employed by the distractor. Through and through pin placement is done for direct distraction using two of mese devices, if necessary. To date, the first method appears to be more difficult, but at times necessary, although little talar tilt is obtained in valgus. The second method, varus, is simple and probably sufficient for diagnostic and operative cases. The Üiird is reserved for extremely resistive cases such as post fracture and/ or dislocations with certain suspected interarticular types of pathology. The capsular and ligamentous structures are tighter in these cases and there may be interarticular synovitis and adhesions. Ankle joints, just as knee and other joints, vary a great deal in their anatomy and physiology. One will encounter some loose ankles and again, very tight ankles, as well as anatomical variations.
Fig. 8: Prototype of new distractor.
Fig. 9: X-ray, AP, for osteochondritis lesion with two wires passed through the trans-malleolar approach for drilling.
Fig. 10: Lateral view of above shows lesion in the mid-portion of the talus which is inaccessible from an anterior or posterior approach, despite full ankle motion.
For general diagnostic use, the lateral or varus method, as stated, is best. The ankle, early in mis study, was not distracted beyond the widest angle as shown by stress films under anesthesia. Later this was of less concern.
Insertion of me pins used for distraction should be 3 cm to 5 cm above me ankle joint in either tibia or fibula. At this level open epiphyses are not in jeopardy. Insertion of the calcaneal pin should be made 1 cm proximal to the distal cortex of the calcaneous and 2 cm from its posterior margin. The distance on the foot can be determined by reference utilizing the preoperative lateral x-ray. With these precautionary measures, the neurovascular structures can be avoided. This should allow adequate room to avoid "cut out" of me pin. Image control, when necessary, and arthroscopic monitoring is employed.
The amount of room for diagnostic probing and operative instrumentation from accessory portals is immeasurably improved. Oblique scopes are also useful in this approach for observation of the posterior compartment. In extremely tight ankles, the intermediate 3.5 mm scopes and smaller instruments are suggested. The flexible scope has been considered, and may be advantageous under special circumstances. The posterior approach on either side of the Achilles tendon, and the points of entry for instrumentation, or camera in most cases, are easily determined by inserting a 2.5 inch, 18 gauge spinal needle. With me use of the small soakable camera, the problem of positioning is easily overcome for any of these approaches, utilizing the positions described above.
Fig. 11: X-ray, lateral view, showing osteochondritis dissecans of the mid-talus with wires again passed trans-malleolarly for drilling.
Arthroscopic anatomy, pamology, and in particular, demonstration of manipulation of the instrumentation, is far more dramatic when viewed through the television monitor than can be described or illustrated by prints.
In approaching me ankle joint through tibial or fibular channels, a 1 mm Kirschner wire is drilled in the proper direction under fluoroscopic and arthroscopic control. Distraction of the joint is applied as needed. Drilling of lesions is usually performed with an 0.062 mm Kirschner wire. The channels may be enlarged up to 1 cm by means of cannulated reamers. Adequate intermittent irrigation of me joint is essential for removal of debris.
When drilling an intact lesion of me mid-portion of the talus, two holes are made, parallel or slightly converging in the lateral plane. Tlie talus is then flexed and extended and a double row of four or more holes are made as the case may indicate. Prior to this, access by arthroscopic means (needle scope) was tried by the aumor from anterior and posterior to the malleolus and was often found inadequate. In addition, the neurovascular bundle on the medial side was at risk. This then left the undesirable alternative of either medial or lateral malleolar osteotomy or a "take down" of the Achilles tendon. The larger channels are used to pass curettes, burrs and power instruments for debriding craters of osteochondritis dissecans or fracture defects. Flexion and extension of the talus provides good access on either side of the ankle when using these approaches.
Fig. 12: X-ray showing healing of the AP view.
This technique has been expanded for use in the lateral ankle reconstruction with bank fascia lata, as well as for ankle arthrodesis with bank bone again.
A word of caution is felt advisable from the author's experience in the original series of 69 cases. Also, as more sophisticated operative techniques are employed, complications should be anticipated and prevented. For example, when operating, as opposed to diagnostic cases, and triangulating from the two anterior approaches, the possibility of sinus formation and infection increases. In the entire 81 cases in this total series, there were three minor sinus tracks that responded to conservative treatment. One chronically infected sinus track required excision at a later date. This appeared to be due to the trauma of the repeated passage of instruments through the portals where soft tissue is quite minimal between the skin and synovial lining of the joint. Therefore, the technique which we are accustomed to using in the knee should not be applied to the ankle.
The danger of instrument breakage is another problem. Special care should be taken, therefore, regarding instrumentation and wound closure. Perhaps, splinting for a few days postoperatively is advisable. The use of plastic cannulas, as shown, has reduced this hazard immeasurably (Fig. 16). There was one case of sensory nerve damage and one local infection (above) in the first series of 69. Extravasation of fluid into the compartments of the leg occurred several times, but was never considered a problem. This should, however, be watched closely because of the potential danger.
Fig. 13: Diagram showing arthroscopic method of drilling lesion as demonstrated above by the trans-fibular approach with two wires through larger drill holes in the ankle. The talus, or the ankle joint, is flexed and extended to allow about eight holes side by side to be drilled to replenish the blood supply. The technique was done under cineoradiographic and arthroscopic control.
Care to prevent cutting out of the pin and ligament rupture should be observed. If the trans-malleolar approaches are employed carefully and properly, there should be no problem regarding the possibility of fracture. If the above criteria are followed with the newer techniques, complications should be rninimized. The author advises a 10 min preoperative scrubbing of the extremities the night before by the patient in these cases, and does not routinely use antibiotics.
The results of the first 69 cases, the 12 reported above and those in the ensuing year will be analyzed and reported in detail. The point wished to be emphasized is that with these new techniques diagnosis will be more easily made and the treatment of these pathological entities, as shown above, has produced significant and satisfactory degrees of relief to date. Eleven of 12 improved significantly. Four were excellent, four very good, two were fair and one was poor.
Fig. 14: Anterior portals.
Case 1, WC. For the past two years this 16 year old boy has had a history of chronic pain and swelling occurring after sport activities. The Iaminograms showed lesions in the posterolateral compartment of the ankle indicative of synovial chondromatosis, stage I. These changes were not seen on routine x-rays. An ankle arthroscopy was done in the manner described above. Several loose bodies and reactive synovitis were seen. The articular cartilage was in excellent condition. A complete debridement was done arthroscopically and the loose bodies removed. The patient was immediately improved and has remained so for the past six months (Fig. 17, 18).
Case 2, JP. This 15 year old girl injured her right ankle in track several months prior to her being seen. Following this injury she had persistent pain, swelling and limitation of motion for several monms. X-rays revealed a chondral defect (osteochondritis dissecans) in me talus and she also had a "hot" bone scan. Ankle arthroscopy was done by the above technique and the defect was reconstructed and debrided anteriorly, as well as to the posterior boundary. She had significant improvement and continued to improve at five monms. It is expected from our experience with this type of lesion in the knees that slow, but progressive, improvement should occur (Fig. 19, 20).
Case 2, MM. This 39 year old man injured his left ankle when he jumped from a garbage truck while working. He was treated conservatively; seven months later when he had pain and no significant relief he returned for examination . X-rays were taken and proved to be negative. The arthroscopy showed a large lesion with a fragment of cartilage which was loose in the posterior lateral tibial plafond. This area was reconstructed, abraded and debrided. Four months later he is completely asymptomatic (Fig. 21, 22).
Fig. 15: Posterior portals.
Fig. 16: Three different sizes of cannulas are shown.
Case 4, LP. This 41 year old man sustained an undisplaced fracture of the lateral malleolus several months prior to being seen by the author. He was treated conservatively for five weeks in a cast and men ambulated with crutches. This was followed by continual pain for the next six montiis over the lateral aspect of the foot and ankle. X-rays were not remarkable, but arthroscopy showed a bone fragment (osteophyte covered with cartilage and chronically inflamed synovium) attached to the lateral malleolus. This was excised arthroscopically, as per the above method, and the patient improved immediately and returned to work (Fig. 23, 24).
Fig. 17: AP arthrogram showing a symptomatic case of synovial chondromatosis of the ankle with the lesion in the posterolateral compartment of the ankle. All previous routine x-rays were negative. Relief was obtained upon debridement and removal of loose bodies.
Fig. 18: Lateral arthrogram showing same case with lesions in the posterolateral location.
Fig. 19: X-ray of the ankle joint with chondral defect in lateral dome with difficult accessibility.
Fig. 20: Arthroscopic view of crater after reconstruction and drilling.
Summary and Conclusion
The author's experience in ankle arthroscopy has been reviewed. New techniques have been developed for easier and safer accessibility to the ankle joint for diagnostic and surgical procedures, particularly posteriorly. It was noted that more pathology seemed to be found in the ankle joint than previously suspected. It appears that there may be radiolucent and radiopaque chondral lesions undiagnosed and untreated, as well as several forms of the synovial impingement syndrome, such as adhesions, the meniscoid and post-traumatic local synovitis. These pathological entities can be more easily identified and excised with more accuracy and confidence with these methods. These questions, as well as several other questions, remain to be answered. What will the ultimate indications for treatable lesions of the ankle, and what method of treatment will be employed? What will the picture be like after the long-term results are analyzed? Should postoperative care include weight bearing or non- weight bearing, motion or immobilization? Will the flexible scope be of any value in better predicting symptomatic synovial lesions of the ankle? The continued study will help to sort out and answer these questions and others.
Fig. 21: Arthroscopic view of large loose fragment of posterolateral talar plafond.
Fig. 22: Arthroscopic view of FIg. 21 after excision and reconstruction of crater.
Fig. 23: Arthroscopic view of post-traumatic osteophyte in posterolateral corner of the ankle joint.
Fig. 24: Arthroscopic view of lesion after excision.
Laboratory work has been done to establish and document the safety of these techniques. Further added techniques in the future are ankle stabilization and arthrodesis.
A protocol is now formed for a large series under study. Final results can then be reported and submitted, including analysis of the technique(s) described in this preliminary report, as well as the end results of the operative procedures performed. It is expected that this will expand the use of diagnostic and operative arthroscopy of the ankle as a useful and safe technique in our orthopedic practice.
1. Wolin FG. Sidetnan S. LevinthaJ D: Internal derangement of the talar fibular component of the ankle. Surg Gynecol Obstet 1950; 91:193-200.
2. Drez D, Guhl JF. Gollehon D: Ankle arthroscopy technique. J Foot Ankle Surg 1981: 2:138-143.
3. Drez D. Guhl JF, Gollehon D: Ankle arthroscopy: Techniques and indications. Sports Med Clin North Am 1982; 1:35-45.
4. Gollehon D: Arthroscopy of the ankle. Orthopedics. September. 1983.
5 Guhl JF: Techniques on arthroscopic surgery of the ankle, AANA Course. Seattle. WA. December, 1982.
6. Guhl JF: Arthroscopic surgery. Course. Minneapolis. MN. June. 1983.
7. Guhl JF: Arthroscopic surgery. AAOS Course. Seanle. WA. June. 1983.
8. Kelikian AS: Disorders of the Ankle. Philadelphia, WB Saunders Co, 1985.
Section Editor: John J. Joyce III, MD