To compare the clinical efficacy and complication rates between the medial midline and anterolateral portals in ankle arthroscopy for treating medial osteochondral lesions of the talus (OLTs).

We retrospectively analyzed patients with medial OLTs who underwent either a dual medial approach (via the medial midline and anteromedial portal) or a traditional approach (via the anterolateral and anteromedial portal) between June 2017 and January 2023. The degree of injury was evaluated by radiographs, computed tomography, and magnetic resonance imaging. Clinical outcomes were assessed using the visual analog scale (VAS), the American Orthopaedic Foot and Ankle Society (AOFAS) score, and the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) scoring system. The incidence of postoperative complications, including superficial peroneal nerve (SPN) injury, was evaluated in all patients.

There were 39 patients in total; 16 patients underwent the dual medial approach, and 23 patients underwent the traditional approach. The mean age was 39.4 ± 9.0 years, and the mean follow-up duration was 18.7 ± 6.4 months. The clinical outcomes improved significantly in both groups (*P < 0.05), but there was no significant difference between the two groups (P > 0.05). Postoperative complications were mainly SPN injury. The incidence of SPN injury was 13.0% in the traditional approach group and 0% in the dual medial approach group, with no significant difference between the two groups (P > 0.05), but a trend of reduction in SPN injury was observed in the dual medial approach group.

The dual medial approach can also treat medial OLTs well, providing clear visualization and more convenient operation and reducing the possibility of injury to the SPN compared with the traditional approach. Therefore, we consider that the MM portal would be a good alternative to the anterolateral portal in treating medial OLTs.

Osteochondral lesions of the talus are frequent pathologies of the ankle joint. Especially through arthroscopy, the treatment is kept as minimally invasive as possible. However, there are some drawbacks as to the reachability because of the high congruency of the ankle joint. Here, either noninvasive distraction or maximal dorsiflexion may be an option for better access to the lesion. The purpose of this study was to evaluate maximal dorsiflexion compared to neutral position or noninvasive distraction of the ankle joint in the arthroscopic reachability of the talar dome. The hypothesis of this study was that maximal dorsiflexion would allow for greater accessibility of the talar dome compared to neutral position or noninvasive distraction of the joint.

Twenty matched pairs (n=40) of anatomical ankle specimens were used. The effects of neutral position, maximal dorsiflexion, and noninvasive distraction of the ankle joint on arthroscopic accessibility of the ankle joint were tested. After disarticulation of the talus, reach was measured and compared between the 3 positions.

In neutral position, 13.7±1.2 mm of the talar dome was reached laterally and 14.0±1.0 mm medially. In maximal dorsiflexion, the distance was 19.0±1.1mm laterally and 19.8±1.4 mm medially, and in noninvasive distraction it was 16.1±1.5 mm laterally and 15.7±1.0 mm medially. The statistical comparison showed a significantly better reach in dorsiflexion laterally (P = .003) and medially (P = .026).

Accessibility of the talar dome in maximal dorsiflexion was superior to that in neutral position or noninvasive distraction.

Results of this study may allow for better planning in arthroscopic treatment of osteochondral lesions of the talus.

Anterior ankle impingement is a common cause of chronic ankle pain, particularly in athletic populations. Morris and McMurray provided the earliest descriptions of anterior impingement, coining the condition as "athlete's ankle" or "footballer's ankle". The pathology has since been a topic of considerable investigation and has been re-termed "anterior ankle impingement syndrome". Treatment with open surgery has provided good results historically, but at the price of significant complications. Advancements in ankle arthroscopy have decreased the risk of complication drastically and evidence in the literature indicates that anterior arthroscopy is an effective approach to treating osseous and soft tissue impingement. Effective clinical diagnosis and diagnostic imaging are critical for pre-surgical planning. Preoperative detection of anterior osteophytes has been correlated with outcomes. Factors such as joint space narrowing and large osteophytes may also influence outcomes. Therefore, a comprehensive understanding of diagnosis and surgical technique can influence patient outcomes, and patient expectations can be managed around prognostic indicators such as the presence of osteoarthritis. The purpose of this review is to discuss the etiology, clinical presentation, diagnosis, surgical technique, and postoperative rehabilitation of anteromedial and anterolateral anterior ankle impingement syndrome and to evaluate the evidence-based outcomes of arthroscopic management.

Platelet-rich plasma (PRP) and concentrated bone marrow aspirate (CBMA) have the potential to improve the quality of cartilage repair in osteochondral lesions of the talus (OLT). In this review, we describe the basic science and clinical evidence that has been published on the topic of PRP and CBMA on 2 commonly used surgical techniques for the treatment of OLT: bone marrow stimulation and osteochondral autograft transfer.

To investigate anatomic relation of standard and coaxial ankle arthroscopy portals with neurovascular structures during different degrees of ankle motion.

Twenty posterior ankles of ten fresh cadavers were assessed. Posteromedial, posterolateral and coaxial (transmalleolar) portals were created using 4-mm Steinmann pins in accordance with the defined technique in neutral position. The ankles were then dissected, and the distance from the portals to the peroneal tendons, short saphenous vein and sural nerve was measured laterally and that from the tibial nerve, flexor hallucis longus tendon and posterior tibial artery was measured medially. Changes in the distance between these structures were noted in neutral positions, 15° of dorsiflexion and 30° plantar flexion.

In the neutral position, the mean distance of the conventional posterolateral portal to the sural nerve was 6 mm (SD 2.9, range 2.7-14.5). The mean distance of the posterolateral coaxial portal to the peroneal tendon was 1.6 mm (SD 0.55, range 1.1-2.9). The mean distance of the posteromedial portal to the FHL was 2.11 mm (SD 1.1, range 0-4.7). The mean distance of the posteromedial coaxial portal to the posterior tibial artery was 6 mm (SD 1.4, range 3.9-9.5). Although not statistically significant, the distance between the portal and neurovascular structures increased in dorsiflexion for the portals placed posteriorly to the neurovascular structures and increased in plantar flexion for the portals placed anterior to the neurovascular structures.

In comparison with the portals made in the neutral position, the distance between neurovascular structures and portals changes with portal placement in plantar flexion and dorsiflexion. In clinical practice, therefore, it might be safer to place the posteromedial-posterolateral portals in dorsiflexion and posterolateral-posteromedial coaxial portals in plantar flexion. The tibial nerve is closer to the posteromedial coaxial in dorsiflexion and could be in danger if making this portal with the foot in this position.

The aim of this study was to determine which intra-articular injuries are associated with chronic anterolateral pain and functional instability after an ankle sprain.

From 2008 to 2010, records of all patients who underwent ankle joint arthroscopy with anterolateral pain and functional instability after an ankle sprain were reviewed. A systematic arthroscopic examination of the intra-articular structures of the ankle joint was performed. Location and characteristics of the injuries were identified and recorded.

A total of 36 ankle arthroscopic procedures were reviewed. A soft-tissue occupying mass over the lateral recess was present in 18 patients (50%). A partial injury of the anterior talofibular ligament (ATFL) was observed in 24 patients (66.6%). Cartilage abrasion due to the distal fascicle of the anteroinferior tibiofibular ligament coming into contact with the talus was seen in 21 patients (58.3%), but no thickening of the ligament was observed. Injury to the intra-articular posterior structures, including the transverse ligament in 19 patients (52.7%) and the posterior surface of the distal tibia in 21 patients (58.3%), was observed.

Intra-articular pathological findings have been observed in patients affected by anterolateral pain after an ankle sprain. Despite no demonstrable abnormal lateral laxity, morphologic ATFL abnormality has been observed on arthroscopic evaluation. An injury of the ATFL is present in patients with chronic anterolateral pain and functional instability after an ankle sprain. A degree of microinstability due to a deficiency of the ATFL could explain the intra-articular pathological findings and the patients' complaints.

IV.

Ankle arthroscopic procedures offer less postoperative morbidity with faster healing times than open surgical procedures but still have associated risks. Complication rates as high as 17% have been reported. One of the most commonly reported complications is iatrogenic damage to the superficial peroneal nerve, which can result in numbness, tingling, or painful neuralgia. In the present study, we attempted to better assess the location of the superficial peroneal nerve at the ankle to improve preoperative planning and reduce complication rates. Fifty ankle specimens were dissected. A concerted effort was made to classify the location of the superficial peroneal nerve according to the Takao branching pattern, zones of the ankle, and distance to anatomic landmarks. Through our dissections, we found that most ankles have 2 nerve branches at the level of the ankle joint (Takao type II) and that the location of the superficial peroneal nerve branches at the ankle correlated directly with the ankle width. Additionally, 68% of specimens contained a nerve branch located in zone 1, where the anterolateral portal is placed, and 12% had a branch in zone 5, the location of the anteromedial portal site. The results of the present study have confirmed the wide variation in nerve location at the level of the ankle joint and serve to highlight the need for extreme caution during surgical procedures at the ankle.

Arthroscopic treatment of anterior ankle bony impingement provides good results, with a tendency to decrease over time. The purpose of this study was to analyze the factors affecting long-term results.

Eighty consecutive patients with a mean age of 37.3 years were treated between 2000 and 2004. Impingement lesions were identified according to Scranton-McDermott classification. Preoperative ankle osteoarthritis was documented by van Dijk scale upon the x-rays. Bone spurs were analyzed and classified according to location and size. The associated chondral lesions were classified following the International Cartilage Repair Society (ICRS) criteria. Patient data, foot morphology, and previous traumas were recorded. Patients were evaluated after a mean of 104.6 months follow-up with the American Orthopaedic Foot and Ankle Society (AOFAS) scale. The influence of different factors on outcomes was statistically analyzed.

The mean preoperative AOFAS score was 50.9, while at follow-up it was 70.7 (P < .05). The different grades of Scranton-McDermott impingement classification did not affect the results, but the different grades of van Dijk scale significantly affected the result but not the preoperative stage. Tibial localized spurs had better outcome at follow-up. The grade of the chondral lesions significantly affected the outcome. Other factors negatively affecting the results were age, cavus foot morphology, and history of previous ankle fracture.

Arthroscopic treatment provides overall good results, but the long-term presence of associated conditions such as chondral lesions, advanced age, and previous trauma are relevant as prognostic factors. Based on these results, a new classification for bony impingement syndrome system is proposed.

Level IV, case series.

In recent years, minimally invasive surgery has developed and progressed the standard of care in orthopaedics and sports medicine. In particular, the use of posterior hindfoot arthroscopy in the treatment of posterior ankle and hindfoot injury is increasing rapidly as a means of reducing pain, infection rates, and blood loss postoperatively compared with traditional open procedures. In athletes, hindfoot arthroscopy has been used effectively in expediting rehabilitation and ultimately in minimizing the time lost from competition at previous levels. Van Dijk et al were the first to describe the original 2-portal technique, which remains the most commonly used by surgeons today and forms the basis for this review. The current evidence in the literature supports the use of 2-portal hindfoot arthroscopy as a safe, primary treatment strategy for symptoms of posterior ankle impingement, including resection of os trigonum, treatment of flexor hallucis longus and peroneal tendon injury, treatment of osteochondral lesions of the ankle, and the resection of subtalar coalitions. In this review, we present where possible an evidence-based literature review on the arthroscopic treatment of posterior ankle and hindfoot abnormalities. Causes, diagnosis, surgical technique, outcomes, and complications are each discussed in turn.

Hindfoot arthroscopic surgery has been described as a minimally invasive surgical treatment for posterior ankle impingement syndrome. The current article describes a systematic approach for identifying relevant hindfoot structures as well as the clinical results of a case series.

To present a structured systematic surgical approach for identifying relevant anatomic structures and abnormalities during hindfoot arthroscopic surgery. In addition, we report the clinical results of a case series.

Case series; Level of evidence, 4.

The systematic surgical approach divides the extra-articular structures of the hindfoot into quadrants as defined by the intermalleolar ligament. Twenty-two patients underwent hindfoot arthroscopic surgery for the treatment of posterior ankle impingement syndrome. The mean follow-up time was 25 months (range, 14-35 months). Standard patient-reported outcome questionnaires of the foot and ankle outcome score (FAOS) and Short Form-12 (SF-12) general health survey were administered at standard time points after surgery. Return to sporting activities was also calculated as the time period from the date of surgery until the patient was able to participate at their previous level of activity.

The mean FAOS score improved from 59 (range, 22-94) preoperatively to 86 (range, 47-100) postoperatively (P < .01). The mean SF-12 score showed similar improvement with a mean of 66 (range, 42-96) preoperatively to 86 (range, 56-98) postoperatively (P < .01). Nineteen patients reported competing at some level of athletic sport before surgery. All patients returned to their previous level of competition after surgery. The mean time to return to sporting activities was 12 weeks (range, 6-16 weeks). Two complications were reported postoperatively: 1 wound infection and 1 case of dysesthesia of the deep peroneal nerve.

Hindfoot arthroscopic surgery is a safe and effective treatment strategy for posterior ankle impingement syndrome. In addition, it allows the patients a rapid return to sporting activities.

Posterior ankle arthroscopy has traditionally been associated with concern for injury to the posterior tibial nerve and vessels, and this concern is greatest when the patient is positioned supine. Positioning the patient prone could be a safer method for posterior ankle arthroscopy. The purpose of this cadaver study was to determine the anatomic safe zone devoid of vital structures relative to the posteromedial and posterolateral arthroscopic portals created. In addition, exposure of the posterior ankle was evaluated by direct visualization and fluoroscopy to determine the relative utility of these portals. Based on our findings, which are consistent with other previously reported results, we believe that a wide range of ankle pathology can be suited to treatment by means of posterior arthroscopy with the patient in the prone position.

Over the decades, arthroscopy has grown in popularity for the treatment of many foot and ankle pathologies. While anterior ankle arthroscopy is a widely accepted technique, posterior ankle/subtalar arthroscopy is still a relatively new procedure. The goal of this review is to outline the indications, surgical techniques, and results of posterior ankle/subtalar arthroscopy. The main indications include: 1) osteochondral lesions (of subtalar and posterior ankle joint); 2) posterior soft tissue or bony impingement; 3) os trigonum syndrome; 4) posterior loose bodies; 5) flexor hallucis longus (FHL) tenosynovitis; 6) posterior synovitis; 7) subtalar (or ankle) joint arthritis; 8) posterior tibial, talar, or calcaneal fractures (for arthroscopic reduction and internal fixation). Although posterior ankle/subtalar arthroscopy has shown to be safe and effective in the treatment of many of the above mentioned conditions, thorough knowledge of the anatomy, correct indications, and a precise surgical technique are essential to produce good outcomes.

Important progress has been made during the past 30 years in arthroscopic ankle surgery. Ankle arthroscopy has gradually changed from a diagnostic to a therapeutic tool. Most arthroscopic procedures can be performed by using the anterior working area with the ankle in dorsiflexion or plantar flexion; there is no need for routine ankle distraction. Anterior ankle problems, such as anterior impingement syndrome, are approached by anteromedial and anterolateral portals and, if necessary, an accessory portal. Most osteochondral defects can be reached from anterior with the ankle in plantar flexion. For a far posterior location, the osteochondral defect can be approached from posterior. The two-portal hindfoot endoscopic technique (ie, both arthroscopic and endoscopic surgery), with the patient in the prone position, provides excellent access to the posterior ankle compartment and to posteriorly located extra-articular structures.

Simultaneous anterior and posterior ankle impingement has not been previously reported. We identified 62 patients with both anterior and posterior impingement and report the results of anterior arthroscopic and posterior open treatment.

Between January, 1990, and December, 2003, 62 consecutive patients with symptoms and signs of both anterior and posterior impingement of the ankle were identified. Fifty-eight recorded a single injury or multiple ankle sprains. The most common mechanism of injury was inversion or plantarflexion. Initial conservative treatment failed in all patients and anterior arthroscopy and open posterior clearance were done. Followup averaged 11.4 months (up to 5 years). All patients showed posttraumatic synovitis at arthroscopy, and 48 had other arthroscopically-detected lesions, such as anterior tibial plafond lesions, ossicles, or soft-tissue impingement. The posterior arthrotomy revealed a bony cause for impingement in all but four patients, usually an os trigonum or a long posterior process of the talus.

Three patients had anterolateral tenderness after arthroscopy and three had tenderness of the posterior arthrotomy scar. There were no persistent neurologic complications. Fifty-eight patients were available for followup. Forty-seven (81%) had excellent or good outcomes, nine (15.5%) had fair outcomes, and two (3.5%) were graded as poor.

Usually, anterior and posterior impingement occur separately; however, there are patients who have symptoms and signs of both anterior and posterior ankle impingement. A single inversion or plantarflexion mechanism of injury may be responsible for this syndrome, although it may also be caused by repetitive inversion injury. Combined anterior arthroscopic and posterior open treatment obtained good results with minimal complications and morbidity.

In ankle arthroscopy, the joint space of the talocrural joint is often too narrow for insertion of the scope and instruments. Various distraction devices for this procedure have been used to widen the joint space. Bandage distraction is effective and noninvasive, but it is difficult to extend the posterior joint space sufficiently for insertion of the scope. Here we describe a new bandage distraction method that can extend the posterior joint space adequately. Using our method, the anterior and posterior joint spaces on direct lateral radiographs were measured after adding the distraction force in nine healthy volunteers (18 ankles; three men and 6 women). This was compared to a previously reported method. The posterior joint space was widened a greater amount when our new bandage distraction technique was used.

Ankles from 100 cadavers were dissected to evaluate the risk of nerve injury from an arthroscopic procedure. A total of 65 cadavers (104 ankles) were examined to assess the course of the peroneal nerve, and 35 cadavers (77 ankles) were examined for the saphenous nerve (SN). In 82% of specimens, the superficial peroneal nerve ran between the lateral border of the talocrural joint and the peroneus tertius tendon at the talocrural joint level, where the anterolateral portal was placed. Therefore, the superficial peroneal nerve was at high risk for injury with anterolateral portal placement. At the anteromedial portal site, between the medial border of the talocrural joint and the tibialis anterior tendon, the SN coursed an average of 6 +/- 5 mm medial to the medial border of the talocrural joint. SNs in this area were all terminal branches; therefore, anteromedial portal placement avoids nerve injury.

In the dog, as in man and the horse, arthroscopy has an important role in treatment of joint disease. In the shoulder, elbow, and stifle joints, surgical arthroscopy can and should replace the classical surgical methods of treating osteochondrosis lesions. In elbow and tarsocrural joint disorders, the diagnostic potentials of arthroscopy are evident. With the established techniques, not only can the lesions be diagnosed with accuracy, but they can also be treated within the same procedure, making arthroscopy the treatment of choice to deal with osteochondrosis lesions. Without a doubt, arthroscopy will play an important role in the understanding of the etiopathology of different joint diseases, especially within the elbow joint, where so many questions remain unresolved. The advantages of arthroscopy in the diagnosis and treatment of osteochondrosis have also encouraged other veterinary surgeons to adopt the technique. In the developmental stage of arthroscopy in the dog, a frequently expressed comment was that arthrotomy was as valuable and as easy (or easier) to perform as arthroscopy. Now that the advantages of arthroscopy have been demonstrated, the skepticism has changed into enthusiasm. The same evolution is noted with arthroscopy in both man and the horse.

This article reviews previous literature and current conclusions regarding osteochondrosis dissecans in the canine tarsus since it was first reported only 20 years ago. Breed, signalment, and clinical characteristics can greatly aid the clinician in suspicion of this condition. Specific radiographic techniques for confirmation of osteochondrosis are discussed. Treatment options, expectations, and specific surgical approaches are reviewed.

Sixty-two consecutive patients with painful limited dorsiflexion of the ankle not responding to nonoperative treatment participated in a prospective study. All 42 men and 20 women (average age, 31 years) underwent arthroscopic surgery. Preoperative radiographs were graded according to an osteoarthritic and an impingement classification. Standardized followup took place at 4 months and 1 and 2 years after surgery. Results showed that the degree of osteoarthritic changes is a better prognostic factor for the outcome of arthroscopic surgery for anterior ankle impingement than size and location of the spurs. The hypothesis is that osteophytes without joint space narrowing are not a manifestation of osteoarthritic changes but rather the result of local (micro)trauma. After 2 years, 73% of the patients experienced overall excellent or good results; 90% of those without joint space narrowing had good or excellent results, and 50% of those with joint space narrowing had good or excellent results. At the 2-year followup, the group without joint space narrowing showed significantly better scores in pain, swelling, ability to work, and engagement in sports. This study also revealed that patients with less than 2 years of ankle pain before surgery and spurs located anteromedially were more satisfied with the outcome than when longer periods of preoperative pain were involved and when spurs were located anterolaterally.

We reviewed 22 patients who had arthroscopic evaluations and preoperative magnetic resonance imaging studies of their ankles because of chronic anterolateral ankle pain after sprains. The ability of surgeons to use the initial clinical examination to predict arthroscopically confirmed anterolateral ankle impingement was compared with the ability to predict this condition using preoperative magnetic resonance imaging. The patient population consisted of 15 men and 7 women who had an average age of 28 years. Five patients (23%) were intercollegiate athletes and 17 patients (77%) were recreational athletes. All patients reported previous traumas to the involved ankles, and all were seen with chronic ankle pain. Clinical examinations were used to assess ankle pain, swelling, range of motion, and stability. Anterolateral ankle impingement was confirmed in 18 patients (82%) with arthroscopic examination. Clinical examinations had a sensitivity of 94% and a specificity of 75% for predicting impingement, and magnetic resonance imaging had a sensitivity of 39% and a specificity of 50%. The results of this study suggest that preoperative magnetic resonance imaging examination is not beneficial or cost-effective in the diagnosis of anterolateral ankle impingement; furthermore, its use may cause further delay in treatment.

Nine fresh cadaver ankle joints underwent arthroscopy to determine effectiveness of a small diameter, disposable, fiberoptic arthroscope. A sequential examination of the joint was performed through routine anteromedial and anterolateral portals. The anterior aspect of the joint with all anatomical structures was well visualized via the two anterior portals. The posterior aspect of the joint was also well visualized via anterior portals without distraction due to the flexibility of the scope and its small diameter. The quality of the visualization of the posterior joint from the anterior portals alone was comparable to that from the posterior approach. The results of this study indicate that diagnostic arthroscopy of the ankle joint with this disposable 1.6-mm arthroscope is comparable to the standard 2.7-mm to 5-mm arthroscopes. The size, flexibility, and 30 degrees viewing angle of this scope allow excellent and thorough joint visualization by routine anterior portals and minimize the need for joint distractors and posterior portals during routine diagnostic ankle arthroscopy.

Adequate distraction can be obtained in ankle arthroscopy by placing a Steinmann pin transversely in the calcaneus and using the fracture table in a hip or tibial nailing mode. A sterile traction bow is attached to the calcaneal pin and then to the traction crank apparatus of the fracture table. Gross traction is first applied through the leg in the usual manner and then fine traction tension may be increased or decreased intraoperatively through the traction crank. This method of using the fracture table is easy to perform and is familiar to the orthopaedist, as it is used in intramedullary nailing procedures. The primary advantage is that it allows for excellent exposure while avoiding the morbidity associated with a distraction pin through the distal tibia.

The purpose of this study was to determine the position and relative safety of the anterior, posterior, and newly defined middle portals by measuring their distance from the neurovascular structures and tendons on the lateral side of the foot and ankle. Furthermore, this study demonstrates specific components of the posterior subtalar joint and arthroscopic access to each utilizing a technique that allows direct anatomic correlation. The 15 specimens were divided into three groups of five feet each, with one arthroscopic portal site and one instrumentation portal site per group. Group I used the anterior portal for the arthroscope and the posterior portal for the curette. Group II used the posterior portal for the arthroscope and the anterior portal for the curette. In group III, the arthroscope was inserted through the anterior portal and the curette through the middle portal. The sural nerve and small saphenous vein were at risk with posterior portal placement. The anterior portal presented a minor risk of injury to the dorsal intermediate cutaneous branch of the superficial peroneal nerve. The middle portal was without risk to surrounding structures. Group I provided the best access to the posterior facet of the subtalar joint. Group II provided excellent arthroscopic visualization of the posterior facet, but poor access for instrumentation via the anterior portal. Group III provided the best access to the sinus tarsi. No combination of portals allowed visualization or instrumentation of the middle or anterior facets.

Ankle arthroscopy has rapidly become an important diagnostic and therapeutic procedure. Currently, indications for operative arthroscopy include transchondral talar dome fractures, acute articular fractures with hemarthrosis, posttraumatic synovitis, loose bodies, inflammatory synovitis, degenerative joint disease, and soft tissue impingement. Diagnostic arthroscopy is indicated for the patient with a chronically painful, symptomatic ankle when nonoperative treatment has failed and other measures have failed to produce a diagnosis. Three standard portals are used for routine ankle arthroscopy and allow a systematic examination of the joint. Mechanical distraction may be required to visualize the entire joint, the tight ankle, the ankle with posterior lesions, or to allow operative instruments to be introduced. The use of lasers in arthroscopy has yet to be clearly defined. The small size of the laser is an advantage in the ankle, but cost remains a disadvantage. Advances in technique and equipment will continue to expand the indications for this procedure.

Twenty-nine cases of operative arthroscopy of the ankle were done between 1985 and 1989 for synovial impingement of the ankle. The average age of the patients was 37 years. All patients (17 men, 12 women) reported an earlier history of injury, with 24 of the patients (83%) noting chronic ankle pain after an inversion injury and 5 of the patients (17%) reporting a previous ankle fracture. Physical examination elicited anterolateral tenderness at the ankle in all cases with associated anteromedial pain in 4 patients. A demonstrable "click" was evident in 6 of the patients (21%) on forced dorsiflexion of the ankle. All patients failed conservative treatment including physical therapy and nonsteroidal antiinflammatory drugs. Surgery was performed at an average of 36 months postinjury. Ankle arthroscopy revealed extensive hypertrophic synovial thickening and scar tissue anterolaterally, indicating synovial impingement in all patients. Associated chondromalacia of the distal tibia was seen in 21% of the patients. Operative arthroscopy included partial synovectomy and debridement of the hypertrophic tissue and partial shaving chondroplasty of the tibia when indicated. Postoperatively, patients were weightbearing as tolerated. Results were assessed subjectively and objectively. At 25-month followup 26 patients had excellent or good results and 3 had fair results; there were no poor results. There were no major complications, including infection or neurovascular compromise. The 3 patients with associated ankle instability comprised the "fair" result group and eventually required lateral ankle reconstruction. Thus, chronic ankle pain due to synovial impingement can be safely, predictably, and effectively treated by operative ankle arthroscopy.

Numerous anatomic structures are at risk when performing ankle arthroscopy through the more commonly utilized portals. The purpose of this paper was to demonstrate the relative safety of each of the arthroscopic portal and Acufex external ankle distractor pin sites by measuring their proximity to the neurovascular structures surrounding the ankle joint. Six fresh cadaver specimens and 12 fresh-frozen, below-knee amputations were utilized for this study. An Acufex ankle distractor was applied using the standard technique. Anteromedial, anterolateral, anterocentral, posterolateral, and posteromedial portals were placed using an 11-blade scalpel to make 5-mm longitudinal incisions. The joint capsule was penetrated and a 3-mm arthroscope was placed into the ankle joint. The skin surrounding each of the portals was carefully removed and the proximity of any nerves or vessels was measured with respect to the arthroscope. At least one incidence of contact or penetration of a nerve or vessel was noted for each site. The anterocentral portal was at greatest risk for nerve or vessel damage. The anterolateral, anteromedial, and posterolateral portals were the safest areas for portal placement, with no penetration of neurovascular structures in any case.

We compared the difference in operative time, hospitalization and recovery time in two groups of patients who underwent open or arthroscopic resection of anterior, tibiotalar, impinging spurs. The operative time was approximately the same, but the average length of hospitalization and time to recovery were shorter in the arthroscopic group. A classification system is proposed that grades the degree of spur formation and assists in predicting the length of recovery time and whether the patient is a candidate for open or arthroscopic spur resection. In this series, grade I spur patients recovered and resumed full activity at 5.0 weeks, grade II at 5.6 weeks, grade III at 6.4 weeks, and grade IV at 10.0 weeks postoperatively. Grade IV patients are not suitable candidates for an arthroscopic debridement.

We studied 31 patients (17 females, 14 males; average age, 34) with more than 2 years of followup who had chronic anterolateral ankle pain following inversion injury. All had failed to respond to at least 2 months of conservative treatment and had negative stress radiographs to rule out instability. On physical examination, tenderness was localized to the anterolateral corner of the talar dome. Magnetic resonance imaging was the most useful diagnostic screening test, showing synovial thickening consistent with impingement in the anterolateral gutter. At an average of 24 months after injury, all patients underwent ankle arthroscopy, which showed proliferative synovitis and fibrotic scar tissue in the lateral gutter, often with associated chondromalacia of the talus. Operative arthroscopic treatment consisted of partial synovectomy with debridement of scar tissue from the lateral gutter. Postoperatively, patients walked with crutches allowing weightbearing as tolerated. Average return to sports was 6 weeks. Histopathologic analysis performed on the resected tissue showed synovial changes consistent with chronic inflammation. Results of treatment after at least 2 year followup were 15 excellent, 11 good, 4 fair, and 1 poor. Since there are several distinct causes of chronic ankle pain, we prefer to call this problem "anterolateral impingement of the ankle" and believe the term "chronic sprain pain" should be discarded.

Abnormalities of the foot and ankle can be difficult to diagnose by conventional examination and x-rays. Recently, magnetic resonance imaging (MRI) has emerged as a diagnostic tool for soft tissue and bony imaging. One hundred and ten normal feet and ankles were studied to define normal MRI anatomy. An additional 150 MRI scans were performed to diagnose and characterize various abnormal conditions. MRI demonstrated excellent definition of normal structures and pathologic entities. Surgical correlation with the MRI was done in 42 patients. MRI appears to be a useful examination for patients with certain soft tissue and bony abnormalities. A special oblique view also has been developed to assist in the diagnosis of injuries to the tibialis posterior, flexor hallucis longus, and flexor digitorum longus tendons.