Arthroscopy: The Journal of Arthroscopic and Related Surgery 8(3):363-365
Published by Raven Press, Ltd. 0 1992Arthroscopy Association of
North America
Case Report
A Potential Complication of Endoscopic Tunnel Release
Carpal
James F. Scoggin, D.V.M., M.D. and Terry L. Whipple, M.D., F.A.C.S.
Summary:
Complications
of carpal tunnel release have been well documented
in the literature. Recently, a procedure for endoscopic release of the transverse carpal ligament has been described. This case report demonstrates a potential complication of endoscopic carpal tunnel release, in which the flexor digitorum superticialis tendon to the ring finger was nearly cut when the arthroscopic trocar passed beneath it. The procedure was converted to an open carpal tunnel release when the transverse fibers of the carpal ligament were not seen after several passes of the trocar. This complication was related to the inability to fully extend the wrist and metacarpophalangeal joints because of arthritic contractures. This case underscores the need for accurate identification of endoscopic anatomy prior to release of the carpal tunnel. The surgeon should not hesitate to convert to open technique if it becomes necessary. Key Words: Carpal tunnel syndrome-Endoscopic release-Carpal ligament-Surgery complications.
Surgical release of the transverse carpal ligament for carpal tunnel syndrome has become a common procedure since the first surgical release was reported in 1933 (1). Although the procedure has been generally successful, there have been numerous published reports of complications (2-5). These include: (a) incomplete division of the transverse carpal ligament, (b) injury to the palmar cutaneous branch of the median nerve, (c) injury to the thenar branch of the median nerve, (d) hypertrophic scars, (e) loss of motion of the interphalangeal joints, (f) neuroma formation, (g) dysesthesia of the median
nerve, (h) reflex sympathetic dystrophy. (i) bowstringing of the flexor tendons, Q) hematoma formation, and (k) infection. Chow (6), Okutsu (7), and Agee (8) have described techniques for endoscopic release of the transverse carpal ligament. In 1990, Chow (9) reviewed 149 carpal tunnel decompressions performed endoscopically on 109 patients. In his series there were no permanent neurologic, vascular, or tendon injuries, and no infections or hematomas. The only complication was a temporary ulnar nerve palsy in one patient, which resolved spontaneously. Okutsu (7) reported one recurrent case, and three subcutaneous hematomas. Our article presents another potential complication of endoscopic carpal tunnel release.
From Orthopaedic Research of Virginia, Richmond, Virginia (J.F.S.; T.L.W.) and Bowman Gray School of Medicine, Wake Forest University, Richmond, Virginia, U.S.A. Clinical Fellow, Orthopaedic Research of Virginia (J.F.S.); President, Orthopaedic Research of Virginia (T.L.W.); Clinical Professor of Orthopaedic Surgery, Bowman Gray School of Medicine (T.L.W.). Address correspondence and reprint requests to Dr. Terry L. Whipple, at Orthopaedic Research of Virginia, 8919 Three Chopt Road, Richmond, VA 23229, U.S.A.
CASE REPORT A 75year old woman presented with numbness and pain in her right hand in a classic median nerve
363
364
J. F. SCOGGIN AND T. L. WHIPPLE
distribution. She also had pain and limited extension of her wrist and metacarpophalangeal (MCP) joints. Wrist extension was limited to 20”, and MCP extension to -30”. Eiectromyography and nerve conduction studies were subsequently performed, which confirmed the clinical diagnosis of carpal tunnel syndrome. Roentgenograms revealed evidence of pantrapezial arthritis, radiocarpal arthritis, (CMC) arthritis, as well as MCP and interphalangeal (IP) joint degenerative changes. The patient was initially treated conservatively, with physical therapy modalities, nonsteroidal antiinflamatory drugs (NSAIDs), and a cock-up wrist splint. After 3ti months of treatment, she returned with worsening symptoms, and elected to proceed with an endoscopic carpal tunnel release. The procedure was performed using the technique described by Chow (6). Bier-block anesthesia was used. Surgical landmarks were drawn on the wrist and hand. An incision was made -1 cm proximal and 1 cm radial to the prominence of the pisiform bone. The fascia was incised, and the interval between the ulnar neurovascular bundle and the flexor tendons was identified. The arthroscopic sheath and blunt trocar were inserted while the flexor tendons were retracted radially. The wrist and fingers were maximally extended and strapped to the extension frame. The trocar was advanced distally into the palm of the hand. An exit incision was made at the intersection of two lines, one formed by the distal border of the thumb, and the second, perpendicular line, through the third web space. The scope was inserted into the sheath and transverse fibers were identified on the deep surface of the transverse carpal ligament. These fibers appeared to be more coarsely striated than those seen in previous endoscopic releases (Fig. 1). The trocar and scope were repositioned several times, and the tissues seen through the slotted sheath were repeatedly probed. The transverse fibers that were visualized appeared slightly oblique and coarser than usual, and could not be positively identified. The procedure was converted to an open carpal tunnel release. The trocar and slotted sheath were left in place in the carpal tunnel. When the carpal tunnel was opened, the flexor digitorum superficialis tendon to the ring finger was seen to be tethered over the arthroscopy sheath (Figs. 2 and 3). Failure to recognize this subtle deviation from the normal endoscopic anatomy would have resulted in transection of the tendon.
Arthroscopy,
Vol. 8, No. 3, 1992
FIG. 1. Endoscopic appearance of flexor digitorum superficialis tendon tethered over the arthroscopy sheath. The fibers appear coarser and more oblique than transverse carpal ligament fibers (arrow).
DISCUSSION With any new surgical procedure, reports of complications and suboptimal results are likely to appear as case numbers increase. This process helps to define indications and contraindications for new surgical procedures. In this case, the patient’s severe wrist and hand arthritis limited extension of her wrist and fingers. Failure to achieve full extension allowed the tendon to maintain a more volar position and thus overlap the path of the trocar. Two important points are illustrated by this case report. The first is that endoscopic carpal tunnel release must be performed with caution in patients in whom carpal or MCP joint arthritis limits dorsiflexion of the wrist and fingers. The second is that the endoscopic surgical anatomy must be unequivocally identified prior to incising the transverse car-
FIG. 2. Appearance of flexor digitorum superficialis tendon tethered over the arthroscopy sheath after conversion to open technique.
COMPLICATION
OF ENDOSCOPIC
RELEASE
365
FIG. 3. Schematic representation of trocar position relative to flexor digitorum superlicialis tendon. 0 Susan E. Brust, 1991. Reproduced with permission.
pal ligament. The surgeon should not hesitate to convert to an open carpal tunnel release if the surgical anatomy cannot be satisfactorily demonstrated. REFERENCES Learmonth JR. The principle of decompression in the treatment of certain diseases of peripheral nerves. Surg Cfin Norrh Am 1933;13:905-13. Blair SJ. Avoiding complications of surgery for nerve compression syndrome. Orthop C/in North Am 1988;19:125-9. Eason SY, Belsole RJ, Greene TL. Carpal tunnel release: Analysis of suboptimal results. J Hand Surg [B] 1985;lO: 365-9.
4. Lilly CJ. Magnell TD. Severance of the thenar branch of the median nerve as a complication of carpal tunnel release. J Hand Surg [Am] 1985;3:399-402. 5. Louis DS, Greene TL, Noellert AC. Complications of carpal tunnel surgery. J Neurosurg 1985;62:353& 6. Chow JCY. Endoscopic release of the carpal ligament: A new technique for carpal tunnel syndrome. Arthroscopy 1989;5: 19-24. 7. Okutsu I. Endoscopic management of carpal tunnel syndrome. Arthroscopy 1989;5: I l-8. 8. Agee J, Tortosa R, Berry D, Pimer C. Endoscopic release of the carpal tunnel: A randomized prospective multicenter study. Proceedings of the 45th Annual Meeting of The American Society for Surgery of the Hand, Toronto, Canada, Sept. 1990. 9. Chow JCY. Endoscopic release of the carpal ligament for carpal tunnel syndrome: 22-month clinical results. Arthroscopy 1990;6:288-96.
Arthroscopy. Vol. 8. No. 3, 1992
Published by Raven Press, Ltd. 0 1992Arthroscopy Association of
North America
Case Report
A Potential Complication of Endoscopic Tunnel Release
Carpal
James F. Scoggin, D.V.M., M.D. and Terry L. Whipple, M.D., F.A.C.S.
Summary:
Complications
of carpal tunnel release have been well documented
in the literature. Recently, a procedure for endoscopic release of the transverse carpal ligament has been described. This case report demonstrates a potential complication of endoscopic carpal tunnel release, in which the flexor digitorum superticialis tendon to the ring finger was nearly cut when the arthroscopic trocar passed beneath it. The procedure was converted to an open carpal tunnel release when the transverse fibers of the carpal ligament were not seen after several passes of the trocar. This complication was related to the inability to fully extend the wrist and metacarpophalangeal joints because of arthritic contractures. This case underscores the need for accurate identification of endoscopic anatomy prior to release of the carpal tunnel. The surgeon should not hesitate to convert to open technique if it becomes necessary. Key Words: Carpal tunnel syndrome-Endoscopic release-Carpal ligament-Surgery complications.
Surgical release of the transverse carpal ligament for carpal tunnel syndrome has become a common procedure since the first surgical release was reported in 1933 (1). Although the procedure has been generally successful, there have been numerous published reports of complications (2-5). These include: (a) incomplete division of the transverse carpal ligament, (b) injury to the palmar cutaneous branch of the median nerve, (c) injury to the thenar branch of the median nerve, (d) hypertrophic scars, (e) loss of motion of the interphalangeal joints, (f) neuroma formation, (g) dysesthesia of the median
nerve, (h) reflex sympathetic dystrophy. (i) bowstringing of the flexor tendons, Q) hematoma formation, and (k) infection. Chow (6), Okutsu (7), and Agee (8) have described techniques for endoscopic release of the transverse carpal ligament. In 1990, Chow (9) reviewed 149 carpal tunnel decompressions performed endoscopically on 109 patients. In his series there were no permanent neurologic, vascular, or tendon injuries, and no infections or hematomas. The only complication was a temporary ulnar nerve palsy in one patient, which resolved spontaneously. Okutsu (7) reported one recurrent case, and three subcutaneous hematomas. Our article presents another potential complication of endoscopic carpal tunnel release.
From Orthopaedic Research of Virginia, Richmond, Virginia (J.F.S.; T.L.W.) and Bowman Gray School of Medicine, Wake Forest University, Richmond, Virginia, U.S.A. Clinical Fellow, Orthopaedic Research of Virginia (J.F.S.); President, Orthopaedic Research of Virginia (T.L.W.); Clinical Professor of Orthopaedic Surgery, Bowman Gray School of Medicine (T.L.W.). Address correspondence and reprint requests to Dr. Terry L. Whipple, at Orthopaedic Research of Virginia, 8919 Three Chopt Road, Richmond, VA 23229, U.S.A.
CASE REPORT A 75year old woman presented with numbness and pain in her right hand in a classic median nerve
363
364
J. F. SCOGGIN AND T. L. WHIPPLE
distribution. She also had pain and limited extension of her wrist and metacarpophalangeal (MCP) joints. Wrist extension was limited to 20”, and MCP extension to -30”. Eiectromyography and nerve conduction studies were subsequently performed, which confirmed the clinical diagnosis of carpal tunnel syndrome. Roentgenograms revealed evidence of pantrapezial arthritis, radiocarpal arthritis, (CMC) arthritis, as well as MCP and interphalangeal (IP) joint degenerative changes. The patient was initially treated conservatively, with physical therapy modalities, nonsteroidal antiinflamatory drugs (NSAIDs), and a cock-up wrist splint. After 3ti months of treatment, she returned with worsening symptoms, and elected to proceed with an endoscopic carpal tunnel release. The procedure was performed using the technique described by Chow (6). Bier-block anesthesia was used. Surgical landmarks were drawn on the wrist and hand. An incision was made -1 cm proximal and 1 cm radial to the prominence of the pisiform bone. The fascia was incised, and the interval between the ulnar neurovascular bundle and the flexor tendons was identified. The arthroscopic sheath and blunt trocar were inserted while the flexor tendons were retracted radially. The wrist and fingers were maximally extended and strapped to the extension frame. The trocar was advanced distally into the palm of the hand. An exit incision was made at the intersection of two lines, one formed by the distal border of the thumb, and the second, perpendicular line, through the third web space. The scope was inserted into the sheath and transverse fibers were identified on the deep surface of the transverse carpal ligament. These fibers appeared to be more coarsely striated than those seen in previous endoscopic releases (Fig. 1). The trocar and scope were repositioned several times, and the tissues seen through the slotted sheath were repeatedly probed. The transverse fibers that were visualized appeared slightly oblique and coarser than usual, and could not be positively identified. The procedure was converted to an open carpal tunnel release. The trocar and slotted sheath were left in place in the carpal tunnel. When the carpal tunnel was opened, the flexor digitorum superficialis tendon to the ring finger was seen to be tethered over the arthroscopy sheath (Figs. 2 and 3). Failure to recognize this subtle deviation from the normal endoscopic anatomy would have resulted in transection of the tendon.
Arthroscopy,
Vol. 8, No. 3, 1992
FIG. 1. Endoscopic appearance of flexor digitorum superficialis tendon tethered over the arthroscopy sheath. The fibers appear coarser and more oblique than transverse carpal ligament fibers (arrow).
DISCUSSION With any new surgical procedure, reports of complications and suboptimal results are likely to appear as case numbers increase. This process helps to define indications and contraindications for new surgical procedures. In this case, the patient’s severe wrist and hand arthritis limited extension of her wrist and fingers. Failure to achieve full extension allowed the tendon to maintain a more volar position and thus overlap the path of the trocar. Two important points are illustrated by this case report. The first is that endoscopic carpal tunnel release must be performed with caution in patients in whom carpal or MCP joint arthritis limits dorsiflexion of the wrist and fingers. The second is that the endoscopic surgical anatomy must be unequivocally identified prior to incising the transverse car-
FIG. 2. Appearance of flexor digitorum superficialis tendon tethered over the arthroscopy sheath after conversion to open technique.
COMPLICATION
OF ENDOSCOPIC
RELEASE
365
FIG. 3. Schematic representation of trocar position relative to flexor digitorum superlicialis tendon. 0 Susan E. Brust, 1991. Reproduced with permission.
pal ligament. The surgeon should not hesitate to convert to an open carpal tunnel release if the surgical anatomy cannot be satisfactorily demonstrated. REFERENCES Learmonth JR. The principle of decompression in the treatment of certain diseases of peripheral nerves. Surg Cfin Norrh Am 1933;13:905-13. Blair SJ. Avoiding complications of surgery for nerve compression syndrome. Orthop C/in North Am 1988;19:125-9. Eason SY, Belsole RJ, Greene TL. Carpal tunnel release: Analysis of suboptimal results. J Hand Surg [B] 1985;lO: 365-9.
4. Lilly CJ. Magnell TD. Severance of the thenar branch of the median nerve as a complication of carpal tunnel release. J Hand Surg [Am] 1985;3:399-402. 5. Louis DS, Greene TL, Noellert AC. Complications of carpal tunnel surgery. J Neurosurg 1985;62:353& 6. Chow JCY. Endoscopic release of the carpal ligament: A new technique for carpal tunnel syndrome. Arthroscopy 1989;5: 19-24. 7. Okutsu I. Endoscopic management of carpal tunnel syndrome. Arthroscopy 1989;5: I l-8. 8. Agee J, Tortosa R, Berry D, Pimer C. Endoscopic release of the carpal tunnel: A randomized prospective multicenter study. Proceedings of the 45th Annual Meeting of The American Society for Surgery of the Hand, Toronto, Canada, Sept. 1990. 9. Chow JCY. Endoscopic release of the carpal ligament for carpal tunnel syndrome: 22-month clinical results. Arthroscopy 1990;6:288-96.
Arthroscopy. Vol. 8. No. 3, 1992
