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AN ANTERIOR PORTAL FOR WRIST ARTHROSCOPY. Anatomical study and case reports
AN ANTERIOR PORTAL FOR WRIST ARTHROSCOPY Anatomical study and case reports S. THAM, S. COLEMAN and D. GILPIN From the Hand and Upper Limb Unit, Princess Alexandra Hospital, Woolloongabba, Queensland, Australia
We have found that the standard portals described limit arthroscopic access to and visualization of some areas of the radiocarpal joint. We describe a radial anterior portal, which we believe is useful in the arthroscopic treatment of wrist conditions and describe its use in clinical practice. Journal of Hand Surgery (British and European Volume, 1999) 24B: 4: 445–447 The role of wrist arthroscopy has been vastly expanded beyond its initial use as a diagnostic tool (Chen, 1979). Arthroscopic treatment is now commonly used for various wrist conditions. The standard arthroscopic portals are located on the dorsum of the wrist. We have found that these portals limit visualization of the dorsal aspect of the distal radial articular surface, particularly during arthroscopic radial styloidectomy, arthroscopic synovectomy and arthroscopic reduction of dorsal lip fractures of the radius. Visualization of the anterior aspect of the scapholunate ligament is also restricted with conventional wrist portals. In this study we have examined eight cadaveric wrists to identify an arthroscopic portal on the anterior aspect of the wrist, and include case reports demonstrating its clinical application.
proximal wrist crease. The rod was then left in place and its relation to the adjacent neurovascular structures was identified by dissection. The radial artery and its venae comitantes lay 5 to 6 mm radial to the metal rod and the median nerve was 4 to 5 mm on its ulnar side. Following complete resection of FCR, the rod was seen to exit 8 to 11 mm distal to pronator quadratus. The anterior carpal branches of the radial artery were located at a level just distal to the distal edge of pronator quadratus and 7 to 9 mm proximal to the rod. Clinical trial The anterior portal was established in one patient who underwent fixation of a scaphoid fracture and another patient with an intra-articular fracture of the radius. The exposure used part of the standard anterior approach used for the open treatment of such fractures. The anterior portal was first established using a 2 cm longitudinal incision centered over the FCR tendon at the level of the proximal wrist flexion crease. The tendon was exposed so that it could be retracted out of its sheath. The median nerve and radial artery together with its venae comitantes were identified. The hand was placed in 2.5 kg of traction applied through two finger traps on the index and middle fingers. A 3–4 portal was established and a routine wrist arthroscopy was carried out. The interval between the long radiolunate ligament and the ligament of Testut was identified and the arthroscope advanced to the interval. The camera was removed from the cannula and after ensuring that the wrist remained in a neutral position with respect to radial and ulnar deviation, a 2 mm blunt trocar was inserted to pierce the anterior wrist capsule (Fig 1). The FCR tendon was retracted radialwards and the tip of the trocar identified in the floor of the FCR tendon sheath. An incision was made to allow the trocar to penetrate the tendon sheath easily. The anterior portal was established by reintroducing a cannula over the end of the trocar and advancing the cannula into the joint as the 3–4 cannula was partially withdrawn (Fig 2). The arthroscopic portal allowed good visualization of the scaphoid and lunate fossae of the distal radius and
MATERIALS AND METHODS Cadaver study Eight cadaveric wrists were dissected. In each specimen, the dorsal extensor compartments were dissected and the space between the third (extensor pollicis longus) and fourth (extensor digitorum) compartments identified. A capsulectomy was then done so that the scapholunate articulation, together with its scapholunate interosseous ligament, were exposed. In two wrists, the contents of the flexor compartment were also resected. This was done to allow identification of the anterior wrist capsuloligamentous complex, particularly the radioscaphocapitate (RSC) ligament and the long radiolunate ligament (LRL). A stainless steel rod, measuring 12.5 cm by 2 mm, was inserted from the dorsum of the wrist between the 3–4 compartment and passed through the anterior capsule between the LRL and the ligament of Testut (LT). The rod emerged at the anterior aspect of the wrist through the bed of the flexor carpi radialis (FCR) tendon. In a further six wrists, a standard 3–4 portal arthroscopy was done. Anteriorly the palmar layer of the FCR tendon sheath was split longitudinally to allow retraction of the tendon. The metal rod was inserted from the dorsum of the wrist through the established 3–4 portal. The FCR tendon was retracted radialwards to allow the rod to pierce through the tendon bed at the 445
446
Fig 1
THE JOURNAL OF HAND SURGERY VOL. 24B No. 4 AUGUST 1999
Anterior view illustrating the cannula penetrating the bed of the FCR sheath.
the proximal portion of the dorsal capsule of the radiocarpal joint. It allowed good visualization of the anterior aspect of the scapholunate interosseous ligament but did not allow easy identification of the dorsal radiocarpal ligament as a separate ligamentous structure. The ulnar limit of visualization was the radial attachment of the triangular fibrocartilage. CASE REPORTS From November 1995 to March 1997, the anterior radiocarpal portal has been used by the senior authors (SC, DG) in 14 cases (Table 1). As our confidence with the technique has grown, we have been able to reduce the size of the portal and no longer specifically identify the adjacent neurovascular structures despite the swelling that is often present in patients who have suffered a fracture of the radius. We have had no difficulty in establishing a portal in these cases. There have been no complications relating to the anterior wrist portal although one patient suffered a dorsal superficial radial nerve injury in the establishment of a 1–2 portal for treatment of an intraarticular fracture of the distal radius. DISCUSSION Wrist arthroscopic surgery has become an established diagnostic and therapeutic technique for the treatment of some wrist conditions. We have used arthroscopic techniques in radial styloidectomy, DRUJ hemi-resection, excision of dorsal wrist ganglia, repair of TFC lesions, synovectomy and fixation of intraarticular distal radial fractures. The standard wrist portals are well documented (Abrams et al., 1994; Botte et al., 1989; North and Thomas, 1988). The proximity of the 1–2 and 3–4 portals to the dorsal aspect of the radial articular surface often makes visualization of this area difficult. This, combined
Fig 2
Table 1
The anterior portal is established by inserting the cannula over the trocar as 3–4 portal rod is partially withdrawn.
Conditions in which the anterior portal has been used
Radial styloidectomy Synovectomy Arthroscopic assisted fracture reduction Diagnostic arthroscopy
5 4 3 2
with the technical difficulties due to the close working distance, creates practical problems in dealing with pathology in this area of the wrist. Similarly, the dorso-ulnar portals (4–5, 6R and 6 U) may be used to visualize the dorsal half of the distal radius but the view obtained is often limited by a prominent dorsal synovial fold. Because of these difficulties, previous efforts have been made to identify a safe anterior portal for arthroscopy of the wrist. Jantea et al. (1994) used similar techniques to ourselves, but were unable to demonstrate a safe anterior portal using an inside-out technique. However, in contrast to our study, their intraarticular landmark was lateral to the radioscaphoid ligament rather than medial to the long radiolunate ligament. As a result of their studies, they concluded that a palmar portal could only be established using an outside-in technique using external landmarks to decide its placement. Although they were able to describe four anterior portals for the midcarpal, radiocarpal and ulnocarpal joints, we were concerned about the safety of neurovascular structures in using such approaches. The portal we describe takes advantage of our experience gained from the exposure used for the surgical approach to the scaphoid directly through the bed of FCR. Although the median nerve and radial artery are located nearby we believe that this approach, using the inside-out technique with the intraarticular landmark described, provides a safe anterior portal for the radial aspect of the radiocarpal joint. We reiterate the importance of maintaining the wrist in a neutral position with respect to radial and ulnar
ANTERIOR PORTAL FOR WRIST ARTHROSCOPY
deviation whilst establishing the portal. We recommend that, when learning this technique, the surgeon should use a slightly larger incision and identify the position of both the median nerve and radial artery on either side of the FCR. Although we see some advantages in having an anterior ulnocarpal portal, we believe that the narrow window of safety, combined with the lack of intraarticular markings at arthroscopy, preclude the safe establishment of an ulnar portal by an inside-out technique. Although the radial anterior wrist arthroscopic portal should not be used for routine arthroscopy, in our experience it has proved invaluable in the assessment and treatment of intraarticular conditions particularly dorsal intraarticular fractures of the distal radius and for arthroscopic radial styloidectomy and synovectomy. It improves the access to the radiocarpal joint whilst respecting the requirements for safety necessary in any surgical treatment.
447
Acknowledgment The authors would like to thank Mr Roger Jellicoe of Smith & Nephew Richards (Aus) Pty Ltd for readily providing a 2.5 mm wrist arthroscope and arranging manufacture of the 2 mm rod.
References Abrams RA, Petersen M, Botte MJ (1994). Arthroscopic portals of the wrist: an anatomic study. Journal of Hand Surgery, 19A: 940–944. Botte MJ, Cooney WP, Linscheid RL (1989). Arthroscopy of the wrist: anatomy and technique. Journal of Hand Surgery, 14A: 313–340. Chen YC (1979). Arthroscopy of the wrist and finger joints. Orthopedic Clinics of North America, 10: 723–733. Jantea CL, Fu FH, McCarthy DM, Herndon JH, Horikoshi M (1994). Palmar approaches/portals for arthroscopy of the wrist. Arthroskopie, 7: 225–231. North ER, Thomas S (1988). An anatomic guide for arthroscopic visualization of the wrist capsular ligaments. Journal of Hand Surgery, 13A: 815–822. Received: 3 September 1998 Accepted after revision: 12 February 1999 D. Gilpin FRACS, Brisbane Hand and Upper Limb Clinic, 259 Wickham Terrace, Brisbane, Queensland 4000, Australia. © 1999 The British Society for Surgery of the Hand Article no. jhsb.1999.0166
We have found that the standard portals described limit arthroscopic access to and visualization of some areas of the radiocarpal joint. We describe a radial anterior portal, which we believe is useful in the arthroscopic treatment of wrist conditions and describe its use in clinical practice. Journal of Hand Surgery (British and European Volume, 1999) 24B: 4: 445–447 The role of wrist arthroscopy has been vastly expanded beyond its initial use as a diagnostic tool (Chen, 1979). Arthroscopic treatment is now commonly used for various wrist conditions. The standard arthroscopic portals are located on the dorsum of the wrist. We have found that these portals limit visualization of the dorsal aspect of the distal radial articular surface, particularly during arthroscopic radial styloidectomy, arthroscopic synovectomy and arthroscopic reduction of dorsal lip fractures of the radius. Visualization of the anterior aspect of the scapholunate ligament is also restricted with conventional wrist portals. In this study we have examined eight cadaveric wrists to identify an arthroscopic portal on the anterior aspect of the wrist, and include case reports demonstrating its clinical application.
proximal wrist crease. The rod was then left in place and its relation to the adjacent neurovascular structures was identified by dissection. The radial artery and its venae comitantes lay 5 to 6 mm radial to the metal rod and the median nerve was 4 to 5 mm on its ulnar side. Following complete resection of FCR, the rod was seen to exit 8 to 11 mm distal to pronator quadratus. The anterior carpal branches of the radial artery were located at a level just distal to the distal edge of pronator quadratus and 7 to 9 mm proximal to the rod. Clinical trial The anterior portal was established in one patient who underwent fixation of a scaphoid fracture and another patient with an intra-articular fracture of the radius. The exposure used part of the standard anterior approach used for the open treatment of such fractures. The anterior portal was first established using a 2 cm longitudinal incision centered over the FCR tendon at the level of the proximal wrist flexion crease. The tendon was exposed so that it could be retracted out of its sheath. The median nerve and radial artery together with its venae comitantes were identified. The hand was placed in 2.5 kg of traction applied through two finger traps on the index and middle fingers. A 3–4 portal was established and a routine wrist arthroscopy was carried out. The interval between the long radiolunate ligament and the ligament of Testut was identified and the arthroscope advanced to the interval. The camera was removed from the cannula and after ensuring that the wrist remained in a neutral position with respect to radial and ulnar deviation, a 2 mm blunt trocar was inserted to pierce the anterior wrist capsule (Fig 1). The FCR tendon was retracted radialwards and the tip of the trocar identified in the floor of the FCR tendon sheath. An incision was made to allow the trocar to penetrate the tendon sheath easily. The anterior portal was established by reintroducing a cannula over the end of the trocar and advancing the cannula into the joint as the 3–4 cannula was partially withdrawn (Fig 2). The arthroscopic portal allowed good visualization of the scaphoid and lunate fossae of the distal radius and
MATERIALS AND METHODS Cadaver study Eight cadaveric wrists were dissected. In each specimen, the dorsal extensor compartments were dissected and the space between the third (extensor pollicis longus) and fourth (extensor digitorum) compartments identified. A capsulectomy was then done so that the scapholunate articulation, together with its scapholunate interosseous ligament, were exposed. In two wrists, the contents of the flexor compartment were also resected. This was done to allow identification of the anterior wrist capsuloligamentous complex, particularly the radioscaphocapitate (RSC) ligament and the long radiolunate ligament (LRL). A stainless steel rod, measuring 12.5 cm by 2 mm, was inserted from the dorsum of the wrist between the 3–4 compartment and passed through the anterior capsule between the LRL and the ligament of Testut (LT). The rod emerged at the anterior aspect of the wrist through the bed of the flexor carpi radialis (FCR) tendon. In a further six wrists, a standard 3–4 portal arthroscopy was done. Anteriorly the palmar layer of the FCR tendon sheath was split longitudinally to allow retraction of the tendon. The metal rod was inserted from the dorsum of the wrist through the established 3–4 portal. The FCR tendon was retracted radialwards to allow the rod to pierce through the tendon bed at the 445
446
Fig 1
THE JOURNAL OF HAND SURGERY VOL. 24B No. 4 AUGUST 1999
Anterior view illustrating the cannula penetrating the bed of the FCR sheath.
the proximal portion of the dorsal capsule of the radiocarpal joint. It allowed good visualization of the anterior aspect of the scapholunate interosseous ligament but did not allow easy identification of the dorsal radiocarpal ligament as a separate ligamentous structure. The ulnar limit of visualization was the radial attachment of the triangular fibrocartilage. CASE REPORTS From November 1995 to March 1997, the anterior radiocarpal portal has been used by the senior authors (SC, DG) in 14 cases (Table 1). As our confidence with the technique has grown, we have been able to reduce the size of the portal and no longer specifically identify the adjacent neurovascular structures despite the swelling that is often present in patients who have suffered a fracture of the radius. We have had no difficulty in establishing a portal in these cases. There have been no complications relating to the anterior wrist portal although one patient suffered a dorsal superficial radial nerve injury in the establishment of a 1–2 portal for treatment of an intraarticular fracture of the distal radius. DISCUSSION Wrist arthroscopic surgery has become an established diagnostic and therapeutic technique for the treatment of some wrist conditions. We have used arthroscopic techniques in radial styloidectomy, DRUJ hemi-resection, excision of dorsal wrist ganglia, repair of TFC lesions, synovectomy and fixation of intraarticular distal radial fractures. The standard wrist portals are well documented (Abrams et al., 1994; Botte et al., 1989; North and Thomas, 1988). The proximity of the 1–2 and 3–4 portals to the dorsal aspect of the radial articular surface often makes visualization of this area difficult. This, combined
Fig 2
Table 1
The anterior portal is established by inserting the cannula over the trocar as 3–4 portal rod is partially withdrawn.
Conditions in which the anterior portal has been used
Radial styloidectomy Synovectomy Arthroscopic assisted fracture reduction Diagnostic arthroscopy
5 4 3 2
with the technical difficulties due to the close working distance, creates practical problems in dealing with pathology in this area of the wrist. Similarly, the dorso-ulnar portals (4–5, 6R and 6 U) may be used to visualize the dorsal half of the distal radius but the view obtained is often limited by a prominent dorsal synovial fold. Because of these difficulties, previous efforts have been made to identify a safe anterior portal for arthroscopy of the wrist. Jantea et al. (1994) used similar techniques to ourselves, but were unable to demonstrate a safe anterior portal using an inside-out technique. However, in contrast to our study, their intraarticular landmark was lateral to the radioscaphoid ligament rather than medial to the long radiolunate ligament. As a result of their studies, they concluded that a palmar portal could only be established using an outside-in technique using external landmarks to decide its placement. Although they were able to describe four anterior portals for the midcarpal, radiocarpal and ulnocarpal joints, we were concerned about the safety of neurovascular structures in using such approaches. The portal we describe takes advantage of our experience gained from the exposure used for the surgical approach to the scaphoid directly through the bed of FCR. Although the median nerve and radial artery are located nearby we believe that this approach, using the inside-out technique with the intraarticular landmark described, provides a safe anterior portal for the radial aspect of the radiocarpal joint. We reiterate the importance of maintaining the wrist in a neutral position with respect to radial and ulnar
ANTERIOR PORTAL FOR WRIST ARTHROSCOPY
deviation whilst establishing the portal. We recommend that, when learning this technique, the surgeon should use a slightly larger incision and identify the position of both the median nerve and radial artery on either side of the FCR. Although we see some advantages in having an anterior ulnocarpal portal, we believe that the narrow window of safety, combined with the lack of intraarticular markings at arthroscopy, preclude the safe establishment of an ulnar portal by an inside-out technique. Although the radial anterior wrist arthroscopic portal should not be used for routine arthroscopy, in our experience it has proved invaluable in the assessment and treatment of intraarticular conditions particularly dorsal intraarticular fractures of the distal radius and for arthroscopic radial styloidectomy and synovectomy. It improves the access to the radiocarpal joint whilst respecting the requirements for safety necessary in any surgical treatment.
447
Acknowledgment The authors would like to thank Mr Roger Jellicoe of Smith & Nephew Richards (Aus) Pty Ltd for readily providing a 2.5 mm wrist arthroscope and arranging manufacture of the 2 mm rod.
References Abrams RA, Petersen M, Botte MJ (1994). Arthroscopic portals of the wrist: an anatomic study. Journal of Hand Surgery, 19A: 940–944. Botte MJ, Cooney WP, Linscheid RL (1989). Arthroscopy of the wrist: anatomy and technique. Journal of Hand Surgery, 14A: 313–340. Chen YC (1979). Arthroscopy of the wrist and finger joints. Orthopedic Clinics of North America, 10: 723–733. Jantea CL, Fu FH, McCarthy DM, Herndon JH, Horikoshi M (1994). Palmar approaches/portals for arthroscopy of the wrist. Arthroskopie, 7: 225–231. North ER, Thomas S (1988). An anatomic guide for arthroscopic visualization of the wrist capsular ligaments. Journal of Hand Surgery, 13A: 815–822. Received: 3 September 1998 Accepted after revision: 12 February 1999 D. Gilpin FRACS, Brisbane Hand and Upper Limb Clinic, 259 Wickham Terrace, Brisbane, Queensland 4000, Australia. © 1999 The British Society for Surgery of the Hand Article no. jhsb.1999.0166