Results of treatment of severe carpal tunnel syndrome A retrospective study was undertaken to determine the efficacy of carpal tunnel decompression in patients with advanced carpal tunnel syndrome. The criteria for inclusion in this study were unobtainable median sensory-evoked response and absent or prolonged median motor distal latency. Fifteen hands in 13 patients met these criteria. All patients had symptoms, including pain, weakness, or decreased sensation. Postoperative follow-up averaged 27 months. Symptomatic improvement was obtained in 14 of the IS hands, and sensory-evoked response improved in 13 hands. Preoperative thenar atrophy was present in 10 of the 15 hands and was completely resolved in 2 of the 10 patients. These results indicate that carpal tunnel decompression is of benefitto patients with severe carpal tunnel syndrome. Long-standing symptoms, thenar atrophy, virtual anesthesia, and the absence of demonstrable sensory and motor-evoked responses are not contraindications to surgery. (J HAND SURG 1992;17A:1020-3.)
William B. Nolan III, MD, Daniel Alkaitis, MD, PhD, Steven Z. Glickel, MD, and Stephen Snow, MD, New York, N.Y.
Patients with carpal tunnel syndrome frequently benefit from surgical decompression of the median nerve. 1,2 Clinical and electromyographic improvement has been demonstrated for the average patient with carpal tunnel syndrome. 3-5 However, these study groups have been heterogeneous with respect to severity. Once a patient has progressed to severe thenar atrophy, sensory loss, pain, unobtainable median sensory-evoked response, and unobtainable or severely prolonged median motor distal latency, the prognosis for surgical decompression has been shown to be uncertain. 6-8 This report describes the results of preoperative and postoperative clinical examinations and nerve-conduction studies of IS hands in 13 patients with severe, advanced carpal tunnel syndrome. We conducted this study so that we might better advise patients about their From the SI. Lukes/Roosevelt Hospital Center, Division of Hand Surgery, New York, N,Y. Received for publication Aug. 14, 1991; accepted in revised form Jan. 15, 1992. No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. Reprint requests: William B. Nolan III, MD, Roosevelt Hand Surgery Center, 428 West 59th sc, New York, NY 10019.
3/1137062
1020
THE JOURNAL OF HAND SURGERY
prognosis after surgical decompression for a severe compression neuropathy.
Materials and methods From 1985 to 1990, 22 patients had carpal tunnel release because of severe, advanced carpal tunnel syndrome. The criteria for inclusion in this study were an unobtainable median sensory-evoked response and absent or prolonged median motor distal latency. These patients also had symptoms that included pain, diminished strength, and decreased sensation. At the time of follow-up, two had died, six had moved and could not be located, and one refused to have a follow-up nerveconduction study, leaving IS hands in 13 patients available for follow-up evaluation. There were seven men and six women in the group. The average age was 70 years (range, 52 to 86 years). The duration of symptoms before surgery was more than I year in all patients. The patients were questioned about symptoms of pain, diminished strength, and decreased sensation. These symptoms were graded as none, moderate, or severe, Physical examination before and after surgery included Phalen's test, Tinel's sign, static two-point discrimination, and assessment of thenar muscle atrophy. A timed Phalen's test was positive if paresthesias were present in the median nerve
Vol. 17A, No.6 November 1992
distribution in less than 60 seconds. A Tinel's sign was positive if there were paresthesias in the median nerve distribution with percussion at the wrist. Thenar atrophy was graded as present or absent. All patients in the study underwent surgical division of the transverse carpal ligament through a standard palmar incision. None of the patients had internal neurolysis. All patients were immobilized in plaster casts for 2 weeks postoperatively. The average duration of clinical follow-up from the time of surgery was 23 months, with a range of 13 to 63 months. Nerve-conduction studies were done before and after surgery in all patients. Preoperatively, all patients had absence of a median sensory-evoked response. Median motor distal latency was absent in 2 of 15 and prolonged in 13 of 15. The average length of time from operation to follow-up nerve-conduction study was 31 months (range, 9 to 66 months). Before surgery, the possibility of an opposition transfer was discussed with these patients. Only two elected to have the procedure at the time of carpal tunnel decompression. Clinical results The results are detailed in Table I. All patients improved after surgery. Of the 11 patients with pain preoperatively, all but one noted complete relief after surgery; the one had occasional pain. Thirteen of 15 patients reported a decrease in their sense of weakness during daily activities. Two thirds of the patients had complete resolution of numbness, one fourth had partial resolution, and one patient reported no improvement. All patients had a decrease in at least two of the three symptoms of pain, weakness, or numbness. There were no complete failures of symptomatic improvement. Preoperatively, the Phalen's test was positive in all cases. All but one patient had a negative Phalen's test at the time of postoperative examination. Preoperatively, two thirds had a positive Tinel's sign at the wrist. All 10 had resolution of the Tinel's sign after surgery. Static two-point discrimination was greater than 15 mm in five cases preoperatively. One case showed no improvement. The other four improved to an average of 8 mm. Of the 10 cases with a preoperative two-point discrimination less than 15 mm, the average preoperative measurement was 8 mm, changing to 5 mm postoperatively. Presence or absence of thenar atrophy was chosen as
Results of treatment of severe carpal tunnel syndrome
1021
a criterion because of the lack of an objective method to grade partial improvement in the bulk of thenar muscles. Thenar atrophy was present in 11 of 15 cases preoperatively. At the time of follow-up, 2 of 11 had no evidence of thenar atrophy. In 13 of the 15 cases, however, the patient reported that the hand felt subjectively stronger postoperatively. The average age of the two patients with resolution of atrophy was 58 years, and the average age of patients who showed no improvement was 73 years. The duration of thenar atrophy could not be accurately determined from the history beyond the patients' report that it had been present for more than 1 year in all cases. Results of nerve-conduction study Preoperatively, all patients had unobtainable median nerve sensory distal latencies. Two patients had unobtainable median motor distal latencies. All others had prolonged median motor distal latencies ranging from 4.8 to 15.2 msec. Of nine studies in which segmental conduction was performed, five showed recovery across the wrist and four showed diffuse slowing in the 33 m/sec range. Postoperatively sensory distal latencies returned in 87% of the patients. All but one of the patients had improvement in the median motor distal latency. Of the two patients with an unobtainable motor distal latency preoperatively, one did not improve. In all other patients postoperative distal latencies were 1.7 to 10.8 msec better than the preoperative values (Table ll). All patients except one showed electromyographic improvement in the abductor pollicis brevis muscle. The two patients who had no improvement in sensory distal latency with carpal tunnel release (cases 11 and 13) had some symptomatic improvement and were satisfied with the surgical result. These patients were 68 and 74 years of age. The former had no other medical problems, and the latter had insulin-dependent diabetes. Both reported that their symptoms had been present for more than 10 years. Discussion Previous studies have reported that advancing age has a detrimental effect on nerve regeneration." The findings in this study suggest but do not prove a correlation. It is also possible that other factors, such as degenerative arthritis of the basal joint or a general loss of muscle bulk with advancing age, could contribute to real or apparent thenar atrophy in these cases.
1022
Nolan et af.
Table I. Preoperative and postoperative clinical findings Atrophy Case No.
Months 10 postop study
Hand Right Right Left Left Right Right Left Right Left Right Right Right Right Left Right
I 2 3 4
5 6 7 8 9 10 II 12 13 14 15
Preop
13 13 13 22 18 63 42 40 24 29 13 13 13 19
I
Pain
Postop
+ + + + + +
+ +
+ + +
+
+
+
+
+
+
Preop
Postop
(0,1,2)
(0,1,2)
0 0 0 2 2 2 2
0 0 0 0 0 0 0 0 I 0 0 0 0 0 0
+ +
+
I
IS
The recorded symptoms of pain, weakness, and decreased sensation are graded as none (0), moderate
(1),
2 0 2 2 2 1 1
or severe (2).
Table II. Preoperative and postoperative electrodiagnostic study results Sensory latency (msec)
MOlOr latency (msec) Case No.
Age
I 2 3 4 5 6 7 8 9 10
52 80 80 62 83 86 85 53 79 54 68 69 74 74 74
11 12 13 14 15
Months to POSlOp study
Preop
21 14 14 40 16 66 45 58 24 22 9 13 20 26
9.6 6.6 7.6 11.6 12.6 14.8 6.4 4.8 Unobtainable 15.2 Unobtainable 7.6 14.4
22
13.2
lOA
Postop
Preop
4.1 4.9 4.3 5.2 4.6 5.8 4.4 3.8 3.7 4.4 Unobtainable 3.6 10.8 5 3.4
Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable
I
I
Postop 5.2 5.1 4.4 3.9 3.6 3.5 3.4 3.4 5.1 2.7 Unobtainable 2.9 Unobtainable 4.2 2.7
Segmental conduction latency
Slow Slow Slow Slow
Slow Slow Slow Slow Slow
Thirteen patients and fifteen hands arelisted. *Date op = date of surgery.
The median motor distal latency improved to a normal range in about one half of the hands. The greatest improvement in the distal latency was seen in those hands in which the distal latency was most prolonged preoperatively. The sensory response returned in all but two hands. Of those hands in which segmental median sensory
conduction was performed (palm to finger and wrist to palm), about one half showed diffuse slowing. This suggests a regeneration of the median sensory fibers. The results show that a high percentage of these patients had improvement in their electrophysiologic parameters and excellent symptomatic relief after decompression of the carpal tunnel. Long-standing symp-
Results of treatment of severe carpal tunnel syndrome
Decreased sensation
Weakness
I Postop
Preop
Postop
(0,1.2)
(0,1,2)
(0,1,2)
1 1 1 2 2 1 2 1 2 1 2 1 2 2
0 0 0 1 1 0 1 0 0 0 2 0 2
1 2 2 2 2 2 2 2 2
0 0 1 0 0 1 0 0 0 0 2 0
1
0
Preop (0.1,2)
1
1 2 2 2 2 2
1 1 0
Two-point discrimination (mm)
2.
Postop
3.
Preop 8 >15 >15 6
10 >15 10
10 6 5 20
7 20 7 5
5 6 9 5 5 10 5 5 6 5 20 5
7 8
4.
5.
6.
7.
5
8.
toms, thenar atrophy, virtual anesthesia, and the absence of demonstrable sensory- and motor-evoked responses are not contraindications to surgery.
REFERENCES 1. Phalen OS. The carpal tunnel syndrome: seventeen year
9.
1023
experience in diagnosis and treatment of 654 hands. J Bone Joint Surg 1966;48A:211-28. Thomas JE, Lambert EH, Csuz KA. Electrodiagnostic aspects of the carpal tunnel syndrome. Arch Neurol 1967;16:635-41. HongeIl A, Mattson HS. Neurographic studies before, after, and during operation for median nerve compression in the carpal tunnel. Scand J Plast Reconstr Surg 1971;5:103-9. Le Quesne P, Casey E. Recovery of conduction velocity distal to a compressive lesion. J Neurol Neurosurg Psychiatry 1974;37:1346-51. ShUTT DG, Blair WF, Bassett G. Electromyographic changes after carpal tunnel release. J HAND SURG 1986;IIA:876-80. Schlagenhauff RE, GJasauer FE. Pre- and postoperative electromyographic evaluations in the carpal tunnel syndrome. J Neurosurg 1971;35:314-9. Melvin JL, Johnson EW, Duran R. Electrodiagnosis after surgery for carpal tunnel syndrome. Arch Phys Med 1968;49:502-7. Garland H, Longworth EP, Taverner D, et al. Surgical treatment for the carpal tunnel syndrome. Lancet 1964;1:1129-30. Young L, Wray RC, Weeks PM. A randomized prospective comparison of fascicular and epineural digital nerve repairs. Plast Reconstr Surg 1981;68:89-93.
William B. Nolan III, MD, Daniel Alkaitis, MD, PhD, Steven Z. Glickel, MD, and Stephen Snow, MD, New York, N.Y.
Patients with carpal tunnel syndrome frequently benefit from surgical decompression of the median nerve. 1,2 Clinical and electromyographic improvement has been demonstrated for the average patient with carpal tunnel syndrome. 3-5 However, these study groups have been heterogeneous with respect to severity. Once a patient has progressed to severe thenar atrophy, sensory loss, pain, unobtainable median sensory-evoked response, and unobtainable or severely prolonged median motor distal latency, the prognosis for surgical decompression has been shown to be uncertain. 6-8 This report describes the results of preoperative and postoperative clinical examinations and nerve-conduction studies of IS hands in 13 patients with severe, advanced carpal tunnel syndrome. We conducted this study so that we might better advise patients about their From the SI. Lukes/Roosevelt Hospital Center, Division of Hand Surgery, New York, N,Y. Received for publication Aug. 14, 1991; accepted in revised form Jan. 15, 1992. No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. Reprint requests: William B. Nolan III, MD, Roosevelt Hand Surgery Center, 428 West 59th sc, New York, NY 10019.
3/1137062
1020
THE JOURNAL OF HAND SURGERY
prognosis after surgical decompression for a severe compression neuropathy.
Materials and methods From 1985 to 1990, 22 patients had carpal tunnel release because of severe, advanced carpal tunnel syndrome. The criteria for inclusion in this study were an unobtainable median sensory-evoked response and absent or prolonged median motor distal latency. These patients also had symptoms that included pain, diminished strength, and decreased sensation. At the time of follow-up, two had died, six had moved and could not be located, and one refused to have a follow-up nerveconduction study, leaving IS hands in 13 patients available for follow-up evaluation. There were seven men and six women in the group. The average age was 70 years (range, 52 to 86 years). The duration of symptoms before surgery was more than I year in all patients. The patients were questioned about symptoms of pain, diminished strength, and decreased sensation. These symptoms were graded as none, moderate, or severe, Physical examination before and after surgery included Phalen's test, Tinel's sign, static two-point discrimination, and assessment of thenar muscle atrophy. A timed Phalen's test was positive if paresthesias were present in the median nerve
Vol. 17A, No.6 November 1992
distribution in less than 60 seconds. A Tinel's sign was positive if there were paresthesias in the median nerve distribution with percussion at the wrist. Thenar atrophy was graded as present or absent. All patients in the study underwent surgical division of the transverse carpal ligament through a standard palmar incision. None of the patients had internal neurolysis. All patients were immobilized in plaster casts for 2 weeks postoperatively. The average duration of clinical follow-up from the time of surgery was 23 months, with a range of 13 to 63 months. Nerve-conduction studies were done before and after surgery in all patients. Preoperatively, all patients had absence of a median sensory-evoked response. Median motor distal latency was absent in 2 of 15 and prolonged in 13 of 15. The average length of time from operation to follow-up nerve-conduction study was 31 months (range, 9 to 66 months). Before surgery, the possibility of an opposition transfer was discussed with these patients. Only two elected to have the procedure at the time of carpal tunnel decompression. Clinical results The results are detailed in Table I. All patients improved after surgery. Of the 11 patients with pain preoperatively, all but one noted complete relief after surgery; the one had occasional pain. Thirteen of 15 patients reported a decrease in their sense of weakness during daily activities. Two thirds of the patients had complete resolution of numbness, one fourth had partial resolution, and one patient reported no improvement. All patients had a decrease in at least two of the three symptoms of pain, weakness, or numbness. There were no complete failures of symptomatic improvement. Preoperatively, the Phalen's test was positive in all cases. All but one patient had a negative Phalen's test at the time of postoperative examination. Preoperatively, two thirds had a positive Tinel's sign at the wrist. All 10 had resolution of the Tinel's sign after surgery. Static two-point discrimination was greater than 15 mm in five cases preoperatively. One case showed no improvement. The other four improved to an average of 8 mm. Of the 10 cases with a preoperative two-point discrimination less than 15 mm, the average preoperative measurement was 8 mm, changing to 5 mm postoperatively. Presence or absence of thenar atrophy was chosen as
Results of treatment of severe carpal tunnel syndrome
1021
a criterion because of the lack of an objective method to grade partial improvement in the bulk of thenar muscles. Thenar atrophy was present in 11 of 15 cases preoperatively. At the time of follow-up, 2 of 11 had no evidence of thenar atrophy. In 13 of the 15 cases, however, the patient reported that the hand felt subjectively stronger postoperatively. The average age of the two patients with resolution of atrophy was 58 years, and the average age of patients who showed no improvement was 73 years. The duration of thenar atrophy could not be accurately determined from the history beyond the patients' report that it had been present for more than 1 year in all cases. Results of nerve-conduction study Preoperatively, all patients had unobtainable median nerve sensory distal latencies. Two patients had unobtainable median motor distal latencies. All others had prolonged median motor distal latencies ranging from 4.8 to 15.2 msec. Of nine studies in which segmental conduction was performed, five showed recovery across the wrist and four showed diffuse slowing in the 33 m/sec range. Postoperatively sensory distal latencies returned in 87% of the patients. All but one of the patients had improvement in the median motor distal latency. Of the two patients with an unobtainable motor distal latency preoperatively, one did not improve. In all other patients postoperative distal latencies were 1.7 to 10.8 msec better than the preoperative values (Table ll). All patients except one showed electromyographic improvement in the abductor pollicis brevis muscle. The two patients who had no improvement in sensory distal latency with carpal tunnel release (cases 11 and 13) had some symptomatic improvement and were satisfied with the surgical result. These patients were 68 and 74 years of age. The former had no other medical problems, and the latter had insulin-dependent diabetes. Both reported that their symptoms had been present for more than 10 years. Discussion Previous studies have reported that advancing age has a detrimental effect on nerve regeneration." The findings in this study suggest but do not prove a correlation. It is also possible that other factors, such as degenerative arthritis of the basal joint or a general loss of muscle bulk with advancing age, could contribute to real or apparent thenar atrophy in these cases.
1022
Nolan et af.
Table I. Preoperative and postoperative clinical findings Atrophy Case No.
Months 10 postop study
Hand Right Right Left Left Right Right Left Right Left Right Right Right Right Left Right
I 2 3 4
5 6 7 8 9 10 II 12 13 14 15
Preop
13 13 13 22 18 63 42 40 24 29 13 13 13 19
I
Pain
Postop
+ + + + + +
+ +
+ + +
+
+
+
+
+
+
Preop
Postop
(0,1,2)
(0,1,2)
0 0 0 2 2 2 2
0 0 0 0 0 0 0 0 I 0 0 0 0 0 0
+ +
+
I
IS
The recorded symptoms of pain, weakness, and decreased sensation are graded as none (0), moderate
(1),
2 0 2 2 2 1 1
or severe (2).
Table II. Preoperative and postoperative electrodiagnostic study results Sensory latency (msec)
MOlOr latency (msec) Case No.
Age
I 2 3 4 5 6 7 8 9 10
52 80 80 62 83 86 85 53 79 54 68 69 74 74 74
11 12 13 14 15
Months to POSlOp study
Preop
21 14 14 40 16 66 45 58 24 22 9 13 20 26
9.6 6.6 7.6 11.6 12.6 14.8 6.4 4.8 Unobtainable 15.2 Unobtainable 7.6 14.4
22
13.2
lOA
Postop
Preop
4.1 4.9 4.3 5.2 4.6 5.8 4.4 3.8 3.7 4.4 Unobtainable 3.6 10.8 5 3.4
Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable Unobtainable
I
I
Postop 5.2 5.1 4.4 3.9 3.6 3.5 3.4 3.4 5.1 2.7 Unobtainable 2.9 Unobtainable 4.2 2.7
Segmental conduction latency
Slow Slow Slow Slow
Slow Slow Slow Slow Slow
Thirteen patients and fifteen hands arelisted. *Date op = date of surgery.
The median motor distal latency improved to a normal range in about one half of the hands. The greatest improvement in the distal latency was seen in those hands in which the distal latency was most prolonged preoperatively. The sensory response returned in all but two hands. Of those hands in which segmental median sensory
conduction was performed (palm to finger and wrist to palm), about one half showed diffuse slowing. This suggests a regeneration of the median sensory fibers. The results show that a high percentage of these patients had improvement in their electrophysiologic parameters and excellent symptomatic relief after decompression of the carpal tunnel. Long-standing symp-
Results of treatment of severe carpal tunnel syndrome
Decreased sensation
Weakness
I Postop
Preop
Postop
(0,1.2)
(0,1,2)
(0,1,2)
1 1 1 2 2 1 2 1 2 1 2 1 2 2
0 0 0 1 1 0 1 0 0 0 2 0 2
1 2 2 2 2 2 2 2 2
0 0 1 0 0 1 0 0 0 0 2 0
1
0
Preop (0.1,2)
1
1 2 2 2 2 2
1 1 0
Two-point discrimination (mm)
2.
Postop
3.
Preop 8 >15 >15 6
10 >15 10
10 6 5 20
7 20 7 5
5 6 9 5 5 10 5 5 6 5 20 5
7 8
4.
5.
6.
7.
5
8.
toms, thenar atrophy, virtual anesthesia, and the absence of demonstrable sensory- and motor-evoked responses are not contraindications to surgery.
REFERENCES 1. Phalen OS. The carpal tunnel syndrome: seventeen year
9.
1023
experience in diagnosis and treatment of 654 hands. J Bone Joint Surg 1966;48A:211-28. Thomas JE, Lambert EH, Csuz KA. Electrodiagnostic aspects of the carpal tunnel syndrome. Arch Neurol 1967;16:635-41. HongeIl A, Mattson HS. Neurographic studies before, after, and during operation for median nerve compression in the carpal tunnel. Scand J Plast Reconstr Surg 1971;5:103-9. Le Quesne P, Casey E. Recovery of conduction velocity distal to a compressive lesion. J Neurol Neurosurg Psychiatry 1974;37:1346-51. ShUTT DG, Blair WF, Bassett G. Electromyographic changes after carpal tunnel release. J HAND SURG 1986;IIA:876-80. Schlagenhauff RE, GJasauer FE. Pre- and postoperative electromyographic evaluations in the carpal tunnel syndrome. J Neurosurg 1971;35:314-9. Melvin JL, Johnson EW, Duran R. Electrodiagnosis after surgery for carpal tunnel syndrome. Arch Phys Med 1968;49:502-7. Garland H, Longworth EP, Taverner D, et al. Surgical treatment for the carpal tunnel syndrome. Lancet 1964;1:1129-30. Young L, Wray RC, Weeks PM. A randomized prospective comparison of fascicular and epineural digital nerve repairs. Plast Reconstr Surg 1981;68:89-93.
