Hip arthroscopy: An anatomic study of portal placement and relationship to the extra-articular structures

The purpose of this study is to accurately describe the relationship of the major neurovascular structures to standard portals used in hip arthroscopy Placement of three standard arthroscopic portals was simulated in eight fresh paired cadaveric hip specimens by placing Steinmann pins into the joint under fluoroscopic control. The specimens were then dissected and the relationship of the portals to the following structures was recorded: lateral femoral cutaneous nerve, femoral nerve, ascending branch of the lateral circumflex femoral artery, superior gluteal nerve, and sciatic nerve. The lateral femoral cutaneous nerve had divided into three or more branches at the level of the anterior portal. The anterior portal averaged only 0.3 cm from one of these branches. The average minimum distance from the anterior portal to the femoral nerve was 3.2 cm. The ascending branch of the lateral circumflex femoral artery averaged 3.7 cm from the anterior portal. A terminal branch of this vessel was present in three specimens 0.3 cm from the portal. The superior gluteal nerve averaged 4.4 cm superior to the anterolateral and posterolateral portals. The sciatic nerve averaged 2.9 cm from the posterolateral portal. From this study, these portal placements appear to be safe. Proper positioning depends on careful attention to the topographical anatomy about the hip. Avoidance of the important structures depends on proper positioning and proper technique in portal placement.     

Posterior ankle arthroscopy portal safety regarding proximity to the tibial and sural nerves

The aim of this cadaveric study was to assess the relative safety of posterior ankle arthroscopy portal sites regarding their distance from the tibial and sural nerves. We dissected 20 embalmed cadaveric lower limbs, carefully exposed the nerves, preserving their original position, and established the entry points of five posterior ankle portals using pins. We measured distances with a digital calliper and used Friedman test and Wilcoxon Signed Ranks tests for statistical analyses. There was unequal safety between the five portals (p = 0.00001). There was no statistically significant difference between the two posterolateral or two posteromedial portals. The trans-Achilles tendon portal as expected was significantly further away from either nerve (p = 0.00001). In conclusion, the trans-Achilles portal is the safest portal in terms of its distance from the nerves but has the disadvantage of surgical injury to the Achilles tendon. The two medial and two lateral posterior portals are equivalent in terms of safety.     

不同体位下肘关节镜常用入路与周围神经的解剖关系

目的 比较不同体位下各种肘关节镜入路与毗邻神经血管的解剖关系,评价肘关节镜操作中各种标准入路的安全性及应用价值.方法 选用新鲜尸体肘关节10个进行解剖,测量9种标准肘关节镜入路与毗邻神经血管的最近距离,并根据各入路下关节镜检的镜下视野及操作灵活性评价其应用价值. 结果肘关节镜人路与毗邻神经距离受注水膨胀关节、肘关节伸直或屈曲及前臂旋前或旋后体位变化影响.肘关节屈曲90°前臂旋后、中立、旋前位,前外侧入路关节镜套管与桡神经距离分别为(2.9±1.1)mm、(4.5±1.5)mm、(5.8 ±1.7)mm,穿刺造成神经损伤风险大;肘关节伸直前臂旋后位2例肘关节中套管与桡神经直接接触.近端前内侧或近端前外侧人路观察肘关节前间室、后正中人路观察后间室视野良好且穿刺风险小.后方入路均安全. 结论近端前内侧或近端前外侧入路优于前内侧或前外侧人路,与后正中入路结合应用可基本满足多数肘关节镜手术的要求,是一组安全、有效的人路点.     

Posterior ankle arthroscopy: an anatomic study

BACKGROUND: Ankle arthroscopy has generally been performed with use of anterior portals with the patient in the supine position. Little has been published on ankle arthroscopy performed with use of posterior portals, particularly with the patient in the prone position. The purpose of the present study was to evaluate the relative safety and efficacy of ankle arthroscopy with use of posterior portals with the limb in the prone position. METHODS: Thirteen fresh-frozen cadaver specimens were used. Posterolateral and posteromedial portals were established. Arthroscopy was performed, and the extent of the talar dome that could be visualized was marked. Four-millimeter plastic cannulae were filled with oil and were placed in the portals for use as reference landmarks on magnetic resonance imaging studies. The proximity of the portal cannulae to the adjacent structures was measured on standard magnetic resonance images and then during careful dissection. The distances measured by dissection were compared with the measurements made on magnetic resonance images. RESULTS: An average of 54% (range, 42% to 73%) of the talar dome could be visualized. The average distance between a cannula and adjacent anatomic structures after dissection was 3.2 mm (range, 0 to 8.9 mm) to the sural nerve, 4.8 mm (range, 0 to 11.0 mm) to the small saphenous vein, 6.4 mm (range, 0 to 16.2 mm) to the tibial nerve, 9.6 mm (range, 2.4 to 20.1 mm) to the posterior tibial artery, 17 mm (range, 19 to 31 mm) to the medial calcaneal nerve, and 2.7 mm (range, 0 to 11.2 mm) to the flexor hallucis longus tendon. The magnetic resonance images demonstrated very similar distances except in the case of the distance between the posteromedial cannula and the tibial nerve, which often was difficult to specifically identify on magnetic resonance imaging studies. CONCLUSIONS: The findings of the present cadaveric study suggest that, with the patient in the prone position, arthroscopic equipment may be introduced into the posterior aspect of the ankle without gross injury to the posterior neurovascular structures. Limited clinical trials should be carried out to confirm this finding.     

Anatomic Study of Anterior and Posterior Ankle Portal Sites for Ankle Arthroscopy in Plantarflexion and Dorsiflexion: A Cadaveric Study in the Japanese Population

Arthroscopy is an important and minimally invasive diagnostic and therapeutic tool. However, the risk of injury to the neurovascular structures around the portals exists during arthroscopy of the ankle. In the present study, we measured the distance between each portal and the adjacent neurovascular structures with the foot in plantarflexion and dorsiflexion in the Japanese population. Standard anterolateral (AL), anteromedial, posterolateral (PL), and posteromedial portal positions were identified in 6 fresh adult cadaveric feet. The skin was dissected from the underlying tissue to visualize the adjacent neurovascular structures as noninvasively as possible. The superficial peroneal nerve was the structure closest to an anterior (i.e., AL) portal (3.2?±?4.2 and 8.3?±?3.9?mm in plantarflexion and 5.2?±?4.3 and 10.8?±?4.1?mm in dorsiflexion), followed by the saphenous nerve and great saphenous vein (SpV). The distance from the superficial peroneal nerve to the AL portal and from the saphenous nerve and great SpV to the anteromedial portal increased significantly with dorsiflexion and decreased significantly with plantarflexion. The sural nerve was the structure closest to the posterior (i.e., PL) portal (10.4?±?4.8?mm in plantarflexion and 8.5?±?3.9?mm in dorsiflexion), followed by the lesser SpV. The distance from the sural nerve, saphenous nerve, and lesser SpV to the PL portal and from flexor hallucis longus, posterior tibial artery, and tibial nerve to the posteromedial portal increased significantly in plantarflexion and decreased significantly in dorsiflexion. These findings could help to prevent damage to the neurovascular structures during ankle arthroscopy.     

Arthroscopic anatomy of the lateral elbow: A comparison of three portals

Ten fresh cadaveric elbows were used to evaluate the proximity of the radial nerve and its branches to three anterolateral portals. A proximal anterolateral portal used routinely at our institution and located 2 cm proximal and 1 cm anterior to the lateral epicondyle was compared with the distal anterolateral portal described by Andrews and with a mid-anterolateral portal. The three portals were initially established without joint distention while the elbows were flexed 90°. Measurements were then obtained with and without joint distention at flexion angles of 0° and 90°. The radial nerve was found to be an average distance of 3.8 mm at extension and 7.2 mm at 90° of flexion from the distal anterolateral portal, located 3 cm distal and 1 cm anterior to the lateral epicondyle. Conversely, the distance between the proximal anterolateral portal cannula and the nerve was statistically greater (p < 0.05), averaging 7.9 mm in extension and 13.7 mm in flexion. The remaining anterolateral portal, located 1 cm directly anterior to the lateral epicondyle, was found to be at a statistically greater average distance from the nerve than was the distal anterolateral portal but statistically closer than was the more proximal portal. The ability to visualize the joint arthroscopically was assessed using the three portals, and although the ulnohumeral joint could be adequately seen using all portals, radiohumeral joint visualization was most complete and technically easiest using the most proximal portal. The proximal anterolateral portal, used in >100 elbow anthroscopies without evidence of radial nerve injury, is recommended for use as the standard lateral access site, allowing excellent visualization while maximizing the distance from the radial nerve throughout the elbow's range of motion.     

经胫后肌腱鞘建立踝关节镜后方共轴入路的解剖学研究

目的进行经胫后肌腱鞘建立踝关节镜后方共轴入路的解剖学研究。方法在20具踝关节标本上以克氏针建立共轴入路,测量克氏针与后方重要神经、肌腱、血管的距离。在5具新鲜踝关节标本上,以2.7mm30°关节镜建立共轴入路,镜下观察并测量以上距离。结果内侧关节镜入路的体表标志为内踝尖上方5～12mm(平均8mm),外侧入路的体表标志为外踝尖上方8～24mm(平均15mm)。经过胫后肌腱鞘、腓骨后缘建立共轴入路,不但把关节镜、镜下器械与后方重要神经血管结构与后关节囊隔开,同时增加了它们之间的距离。经过此入路可以观察到距骨关节面的后1/2～2/3、外侧踝关节间隙、内侧踝关节间隙、后关节囊、胫距关节间隙,能清楚地看到踝穴与距骨的动态关系。可以通过后外侧入路进入手术器械进行镜下手术。结论经胫后肌腱鞘的踝关节镜后方共轴入路,具有操作简便、安全性好、镜下视野清楚、操作空间大的优点。     

Arthroscopy of the elbow: Anatomy,portal sites,and a description of the proximal lateral portal

Cadaveric studies were carried out to evaluate the safety and value of the standard portals used in elbow arthroscopy. The dissections were performed in 12 fresh cadaveric specimens. Each portal was assessed in terms of its safety with respect to nearby important structures. A proximal lateral portal was evaluated and has subsequently been used in 62 patients. A straight posterior (transhumeral) portal was also studied. We have found that in arthroscopy of the elbow joint, the proximal approaches (proximal medial and proximal lateral), are safer than the anteromedial and anterolateral approaches. All areas of the anterior compartment can be visualized using these two portals, and we recommend that they be the standard anterior portals used in elbow arthroscopy. All of the posterior approaches are safe.     

Endoscopic flexor hallucis longus decompression: a cadaver study

BACKGROUND: New indications for arthroscopy are being considered because arthroscopy limits incision size and potentially decreases operative morbidity. This cadaver study investigated the utility of performing an all-endoscopic flexor hallucis longus (FHL) decompression. METHODS: Eight fresh-frozen cadaver legs were used. In the simulated prone position with large joint arthroscopic equipment, posterolateral and posteromedial portals were used to perform posterolateral talar process bony excision and FHL sheath debridement and release. We noted the integrity of the sural nerve, FHL tendon, and medial tibial neurovascular bundle. After open dissection, values for sural nerve distance to the posterolateral portal, the amount of FHL sheath released and the proximity of the arthroscopic instrumentation to the medial tibial neurovascular structures were recorded. RESULTS: Three of eight FHL tendons were injured during the attempted FHL release. Furthermore, no FHL sheath was completely released down to the level of the sustentaculum. Although posterolateral portal placement was on average 12.1 mm from the sural nerve, it was only 6.1 mm from the lateral calcaneal branch of the sural nerve. Moreover, in all cases the medial calcaneal nerve and first branch of the lateral plantar nerve were closely juxtaposed and in some cases adherent to the FHL fibro-osseous sheath. CONCLUSIONS: Although os trigonum or posterolateral talar process excision was performed without difficulty, endoscopic release of the FHL tendon proved technically demanding with significant risk to the local neurovascular structures. Given the reliability and low morbidity of open techniques, this cadaver study calls into question the clinical use of complete endoscopic FHL release to the level of the sustentaculum. Moreover, hindfoot endoscopic surgery should be performed by surgeons familiar with open posterior ankle anatomy and experienced in hindfoot endoscopy.     

Coaxial portals for posterior ankle arthroscopy

Purpose: The authors performed a cadaveric study on 10 ankles and retrospectively reviewed 29 arthroscopic synovectomies to determine the trajectory, minimal safe distances, and complications using a new approach for posterior ankle arthroscopy. Type of Study: Anatomic study and case series. Materials and Methods: A posterolateral portal was established immediately posterior to the peroneal tendon sheath. While staying within the posterior ankle capsule, an inside-out technique was then used to establish the posteromedial portal directly behind the medial malleolus adjacent to the posterior tibial tendon. The cadaveric ankles were frozen, sectioned, and photographed to measure the proximity of neurovascular structures to these coaxial portals. From 1988 to 1994, arthroscopic synovectomy was performed on 23 patients (29 ankles) with hemophilia using these modified portals. Results: Results of the anatomic study showed that the posterior tibial nerve and posterior tibial artery were located a mean distance of 5.7 mm (SEM, 0.6 mm) and 6.4 mm (SEM, 0.7 mm) from the edge of the cannula, respectively. Neither penetration nor contact of nerve or vessel was observed at either posterior portal. In the 29 clinical cases, posterior capsular synovectomy was achieved arthroscopically with no detectable complications at an average 45-month follow-up. Conclusions: Our anatomic data show that the coaxial portals described here are essentially equidistant to the neurovascular structures compared with conventional portals. Our clinical results suggest that his technique for posteromedial and posterolateral portals is safe, effective, and reproducible.     

Anatomical structures at risk in the arthroscopic Broström-Gould procedure: A cadaver study

BackgroundThe Broström Gould procedure is the gold standard for repair of lateral ankle ligament injury and ankle instability. This procedure has demonstrated excellent short- and long-term outcomes in the orthopedic literature. Arthroscopic Broström Gould techniques have become increasingly popular among some foot and ankle orthopedic surgeons. Typically, this technique requires standard anteromedial and anterolateral portals along with an accessory lateral working portal. The exact location of this portal is variable within the available described surgical techniques. The objective of this cadaveric study is to establish a standard entry point for and to assess the safety of the accessory lateral portal with respect to nearby anatomical structures.MethodsTen fresh-frozen below-knee cadaver specimens were used. The location of the accessory lateral portal was created 1.5 cm anterior to the distal tip of the fibula. A small vertical incision was made at this point, followed by insertion of a Kirschner wire into the joint. The wire was then gently impacted into the fibula. Superficial dissection was subsequently carried out around the entry point to identify the peroneal tendons, superficial peroneal nerve branches, and sural nerve branches. Structures were marked with colored push pins, and distance was measured between the nearest edge of the Kirschner wire and each of the three anatomic structures listed. Any instances of structural contact or damage were documented.ResultsThe average distance from the Kirschner wire to the peroneal tendon was 16.1 (±4.41) mm. The average distance from the wire to the superficial peroneal nerve and sural nerve was 13.11 (±6.79) mm and 12.33 (±4.08) mm, respectively. There were no instances of injury to any of the studied structures. However, there was a notable amount of variability in the proximity of structures in question for each cadaver. A branch of the superficial peroneal nerve was measured as close as 2 mm and as far as 24 mm in separate cadaver specimens.ConclusionArthroscopic Broström Gould procedures are a safe and effective method for lateral ankle ligamentous repair but are not without risk. Accessory lateral portal placement is relatively safe but should be meticulously executed to avoid damage to nearby anatomical structures.     

Coaxial portals for posterior ankle arthroscopy: An anatomic study with clinical correlation on 29 patients

Purpose: The authors performed a cadaveric study on 10 ankles and retrospectively reviewed 29 arthroscopic synovectomies to determine the trajectory, minimal safe distances, and complications using a new approach for posterior ankle arthroscopy. Type of Study: Anatomic study and case series. Materials and Methods: A posterolateral portal was established immediately posterior to the peroneal tendon sheath. While staying within the posterior ankle capsule, an inside-out technique was then used to establish the posteromedial portal directly behind the medial malleolus adjacent to the posterior tibial tendon. The cadaveric ankles were frozen, sectioned, and photographed to measure the proximity of neurovascular structures to these coaxial portals. From 1988 to 1994, arthroscopic synovectomy was performed on 23 patients (29 ankles) with hemophilia using these modified portals. Results: Results of the anatomic study showed that the posterior tibial nerve and posterior tibial artery were located a mean distance of 5.7 mm (SEM, 0.6 mm) and 6.4 mm (SEM, 0.7 mm) from the edge of the cannula, respectively. Neither penetration nor contact of nerve or vessel was observed at either posterior portal. In the 29 clinical cases, posterior capsular synovectomy was achieved arthroscopically with no detectable complications at an average 45-month follow-up. Conclusions: Our anatomic data show that the coaxial portals described here are essentially equidistant to the neurovascular structures compared with conventional portals. Our clinical results suggest that his technique for posteromedial and posterolateral portals is safe, effective, and reproducible.Arthroscopy: The Journal of Arthroscopic and Related surgery, Vol 16, No 8 (November-December), 2000: pp 836–842     

Arthroscopic triple fusion joint preparation using two lateral portals: A cadaveric study to evaluate efficacy and safety

BackgroundArthroscopic triple fusion has several advantages over open techniques, but its use has yet to become widespread. Preliminary published techniques use five portals with neurovascular risk. Our aim was to assess the safety and efficacy of an alternative lateral two portal technique.MethodsFour cadaveric hindfeet were arthroscopically prepared for a triple fusion using two lateral portals. The distance to relevant subcutaneous nerves was measured as well as the prepared joint surface percentage.ResultsMean distance from mid-lateral portal to the nearest sural nerve branch was 22.3 mm (range 20–24 mm) and from the dorsolateral portal to the intermediate branch of the superficial peroneal nerve was 7.8 mm (range 4–11 mm). Mean percentages of joint preparation were 63% (talar head), 62% (navicular), 75% (calcaneum) and 74% (cuboid).ConclusionsTwo lateral arthroscopic portals allow adequate joint preparation for triple fusion procedures. The proximity of subcutaneous nerves is important to appreciate when using these portals.     

The new subclavian portal and modified neviaser portal for arthroscopic rotator cuff repair

Shoulder arthroscopy and the introduction of suture anchors has provided the surgeon with the ability to repair rotator cuff tears through minimal incisions. Rotator cuff repair involves the use of several portals, such as the posterior portal, the anterior portal, the anterior superior portal, the anterior inferior portal, and the Neviaser portal. The authors have developed 2 additional portals, the new Subclavian portal and the modified Neviaser portal, to improve the safety and efficacy of rotator cuff repair and solve a number of problems associated with traditional repair techniques. The subclavian portal is located directly below the clavicle, 1 to 2 cm from the acromioclavicular joint, and instruments are aimed medial to lateral. The modified Neviaser portal changes the angle of insertion of the Neviaser portal. Instruments are aimed 20° from the horizontal plane and 45° anterior, directly at the suture anchor. Repair techniques using each portal were reviewed. Twenty cadaveric shoulders were dissected for each portal and the anatomy from each portal was documented. The cadaveric dissections showed that this portal passes greater than 6 cm from the brachial plexus, musculocutaneous nerve, and subclavian artery and vein, and 4.7 cm from the cephalic vein. The modified Neviaser portal was shown to be safer than the Neviaser portal because it passes on top of the supraspinatous muscle, thereby protecting the suprascapular nerve. These portals provide an optimal angle of approach to the rotator cuff tendon and suture anchor as well as improved safety and efficacy in the repair of rotator cuff tears.     

Arthroscopy of the subtalar joint: an experimental approach

Talocalcaneal articulations are relatively complex and functionally very important because they play a major role in the movements of inversion and eversion of the foot. Few reports on arthrography of the subtalar joints are available in the literature, and, similarly, little attention has been paid by arthroscopists to these joints. This preliminary study briefly defines the normal anatomy of the subtalar joints and describes a new technique of arthroscopic examination of the posterior subtalar joint. The distal lower extremities of six fresh cadavers were used in these experiments. All the subtalar joints were supple. A 2.7-mm arthroscope was used to carry out arthroscopic and anatomic examinations. A technique of examination with one anterior portal and one posterior portal is described in detail. When the anterior portal was used, the egress needle was placed posteriorly; when the posterior portal was used, the converse was true. By using the two portals, the following intraarticular structures could be visualized: a major part of the convex posterior calcaneal facet of the talus and the posterior talar facet of the calcaneus; the synovial lining laterally and posteriorly; the posterior aspect of the interosseous talocalcaneal ligament; and the posterior recess of the joint. The results of this experimental study indicate that arthroscopy of the posterior subtalar joint is technically feasible. Clinically, the possible indications for arthroscopy would include state of the articular cartilage in suspected cases of degenerative arthritis, rheumatoid arthritis, and infection; visualization of the joint after intraarticular fracture to evaluate chronic pain syndrome in the hindfoot; biopsy; management of sinus tarsi syndrome; loose body removal.     

Anatomical study of the ankle with view to the anterior arthroscopic portals

This article evaluates the risk of interference with the neurovascular structures in the four anterior ankle arthroscopic portals, described on each side of the extensor tendons: anteromedial, medial midline, anterocentral and anterolateral. Complications after ankle arthroscopies have been described in up to 17%, most being neurovascular. To quantify the neurovascular risks we dissected 68 cadaveric feet and evaluated the correlations between tendons, vessels and nerves. The mean distance between tibialis anterior and extensor hallucis longus and between extensor hallucis longus and extensor digitorum longus is 4 mm, but in 10-20% these tendons are in apposition or are overlapped. The tibialis anterior vascular bundle was absent in 11.8%, was located between the tibialis anterior and the extensor hallucis longus in 3% and between the extensor hallucis longus and the extensor digitorum longus in 64.7%. A peroneal vascular bundle or branches of the tibialis anterior vascular bundle were located lateral to the extensor digitorum longus/peroneus tertius tendon in 88.2%. Transverse vascular branches were identified in 41.2% over the medial side of the joint line and in 52.9% over the lateral side. The deep peroneal nerve was located between the extensor hallucis longus and the extensor digitorum longus tendons in 58.8%. The superficial peroneal nerve had branches located between the tibialis anterior and the extensor hallucis longus tendons in 2.9%, between the extensor hallucis longus and the extensor digitorum longus tendons in 23.5% and lateral to the extensor digitorum longus/peroneus tertius tendon in 32.4%. These results show that the anteromedial and medial midline portals are the safest. The anterolateral portal should be noted not only for the risks to the superficial peroneal nerve, but also to the peroneal vessels.     

Arthroscopic Subtalar Release of Post-traumatic Subtalar Stiffness

We describe an arthroscopic approach of subtalar release for post-traumatic subtalar stiffness that can allow early postoperative vigorous mobilization. The patient is placed in the lateral position. Subtalar arthroscopy is performed via the standard anterolateral portal at the angle of Gissane, the middle portal just distal and anterior to the tip of the lateral malleolus, and the posterolateral portal at the vertical limb of the old surgical scar, just above the posterosuperior tubercle of the calcaneus. Arthroscopic subtalar release is performed in stages. First, the fibrous bands at the sinus tarsi are debrided. The most lateral part of the interosseous talocalcaneal ligament is released. The dense fibrous tissue of the lateral subtalar gutter is then cleared. Most of the time, the subtalar motion gained at this stage is insignificant. At the second stage, the posterior capsule can be released and the fibrous tissue at the posterior corner of the joint can be debrided. Finally, the lateral subtalar capsule and lateral subtalar ligamentous structures are stripped from the lateral calcaneal cortical surface. Stripping should be done beyond the old surgical scar to release the adhesion of the surgical scar to the lateral calcaneal wall.     

Arthroscopy of the elbow joint: A cadaveric study of portal placement

Sixteen fresh cadaver elbows were examined by arthroscopy and dissection to evaluate the usefulness and the anatomic relationships of seven previously described portals for elbow arthroscopy. Most of the examined portals were found to be relatively close to neurovascular structures. The nerves that were found to be located closest to the portals were the posterior antebrachial cutaneous nerve at the direct lateral and antero-lateral portals, the radial nerve at the antero-lateral portal, and the medial antebrachial cutaneous nerve at the high and low antero-medial portals. The degree of flexion and fluid distension of the joint were found to influence the position of nerves and vessels in relation to the arthroscopy portals. At least three different portals were found to be required for thorough examination of the elbow joint. The combination of the low postero-lateral, the direct lateral, and the high antero-medial portals provided the largest visualized area.     

Arthroscopic Approaches to the Ankle Joint

This chapter reviews anterior and posterior arthroscopic approaches to the ankle and subtalar joints. The specific anatomy relevant to arthroscopy is reviewed including the major tendon, vascular, nerve and ligament structures along with the bony anatomy of the joints. A step by step discussion of portal placement, portal establishment, and diagnostic arthroscopy of the joints is presented, first for anterior approaches and then for posterior approaches.