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Treatment of scaphoid nonunion with casting and pulsed electromagnetic fields: A study continuation
Treatment of scaphoid nonunion with casting and pulsed electromagnetic fields: A study continuation This article presents a continuation of a study of the treatment of scaphoid nonunion with pulsed electromagnetic
fields (PEMF) and cast immobilization.
overall success rate for healing has decreased Proximal
pole fractures
evidence of avascular
healed in 50%.
Fifty-four patients were reviewed. The
since the previous review from 80% to 69%.
Success in nonunions
with associated
radiographic
necrosis decreased from 89% to 73%. Although we believe that the in-
dications for use of PEMF have not changed significantly, this study suggests that a successful outcome with PEMF and casting is less likely than previously reported. We believe that until additional clinical studies have further defined the indications, treatment protocol, and efficacy of this method PEMF treatment should be a secondary alternative to bone-grafting procedures. (J HAND SURG 1992;17A:910-4.)
Brian D. Adams, MD, Burlington, Vt., Gary K. Frykman, MD, Loma Linda, Calif., and Julio Taleisnik, MD, Orange, Calif.
N onunited
scaphoids have been managed by numerous methods during the past three decades. Although a displaced scaphoid fracture or a nonunion associated with carpal instability is best managed with open reduction and bone grafting,” 2 uncomplicated nonunion has been successfully treated with electrical stimulation.3-5 Treatment with electrical stimulation is highly controversial, however. This method has not been shown to be consistently better than other nonoperative methods.6, ’ In addition, further skepticism is caused by a poor understanding of the biologic mechanisms of electrically induced osteogenesis. Despite the lack of controlled experimental studies to substantiate the efficacy, electrical stimulation has been used clinically for the treatment of scaphoid nonunion.
From the Department of Orthopaedics and Rehabilitation, University of Vermont, Burlington, Vt., and the Department of Orthopedic Surgery, Loma Linda University School of Medicine, Loma Linda, Calif. Received for publication Jan. 20, 1992.
May 31, 1991; accepted
in revised form
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: Brian D. Adams, MD, Department of Orthopaedics and Rehabilitation, University of Vermont, Burlington, VT 05405. 311136951
910
Early methods of electrical stimulation required invasive procedures53 ’ and therefore offered few advantages over a bone-grafting procedure. With the introduction of the pulsed electromagnetic field (PEMF) with external coils, the advantages of a noninvasive technique that can be applied in the office were apparent.’ However, only a few studies have reported the results of PEMF treatment for scaphoid nonunion.“.” This article presents a continuation of a cIinicaI study of the treatment of scaphoid nonunion with PEMF and casting. Clinical and anatomic findings that may affect the union rate were evaluated. Materials
and methods
We reviewed all cases of scaphoid nonunion treated with PEMF and casting from 1979 to 1989. This represents the combined material of the previous study” and additional cases treated since that report. Because radiographic interpretation of the healing scaphoid can be difficult, further follow-up of available patients from the previous study was performed to assess the status of their supposed union. To be included in this study, the scaphoid fracture had to be at least 6 months old and a standardized protocol of treatment had to be followed. Regardless of previous treatment methods, no operation had been performed during or just before initiation of PEMF treatment. None of the patients had displacement or
Vol. 17A, No. 5 September 1992
significant angulation at the nonunion site, and none showed arthritis of the periscaphoid joints. Three patients reported in the previous series showed loss of carpal alignment, with a dorsal intercalated segment instability pattern before treatment. Since the outcome of treatment in these patients was poor, it was concluded that carpal instability associated with a scaphoid fracture is a contraindication to PEMF and casting alone. This is in agreement with other reports describing the treatment of scaphoid fractures complicated by carpal instability. ‘, 13.I4 Except for the exclusion of patients with carpal instability, there was no change in the inclusion criteria. In the present study a series of consecutive cases were treated by the recommended product protoco1.‘5 External PEMF coils were centered over the scaphoid and attached to either a long arm thumb spica cast or a short arm thumb spica cast. To be included in the final analysis, all patients had to be treated either until the fracture healed or for at least a 3-month period. Sixty-two patients were initially treated. Three patients failed to return for follow-up examination after discontinuation of PEMF treatment. Although their fractures had healed, these patients were excluded from the final analysis. Five additional patients were excluded from the study because they received inadequate treatment of 2 months or less of electrical stimulation. The remaining 54 patients were treated according to the protocol and were available for review. This represents the 44 patients reported previously and 10 additional patients, with further follow-up on 11 of the first 44 patients. There were 51 males and 3 females with an average of 26 years (range, 14 to 46 years). The nonunion site was in the proximal third in 10 patients, in the middle third in 41, and in the distal third in 3 patients. Ten patients had had one previous bone-graft operation, and two patients had undergone two previous operations before initiation of PEMF and casting. Eleven patients showed radiographic evidence of avascular changes in the proximal fragment. The average time from injury to treatment was 35 months, with a range of 6 to 241 months. All patients who were included in the final review were examined from 1 to 33 months after the treatment was stopped, for an average follow-up of 8’/2 months. Plain radiographic evaluation was the standard method used for the initial assessment of nonunion as well as for the final determination of healing status. Anteroposterior, lateral, and scaphoid views were available for each case. Although tomograms and arthrograms were obtained in some cases, these studies were not used for the initial and final assessments in this review.
Treatment of scaphoid nonunion
911
Results The nonunions healed in 37 (69%) of the 54 patients. Five (50%) of the ten nonunions in the proximal third healed, and 32 (73%) of the 44 nonunions in the middle and distal thirds healed. In those patients with evidence of avascular changes of the proximal fragment before PEMF and casting treatment, eight of eleven (73%) nonunions healed. Eight of 12 patients who had undergone previous bone-grafting operations healed. Of the 11 patients who had been followed up since the last report, two were found to have x-ray evidence of nonunion that had been previously interpreted as healed. Thus either a refracture had occurred or an inaccurate assessment of fracture healing had been made. These patients were included in the failed group for the present analysis; this changed the healing rate in the original 44 patients from 80% to 75%. Only four of the ten additional patients achieved union. For the patients in whom nonunion healed, the average duration of electrical stimulation was 4 months, with a range of 2.5 to 9 months. Four patients had PEMF and casting for more than 6 months. In five patients records did not indicate whether an above-elbow or a below-elbow cast was used. In the remaining 49 patients, healing occurred in 24 (83%) of the 29 who were treated with a long arm thumb spica cast and in 13 (59%) of the 22 who were treated with a short arm thumb spica cast. The duration of immobilization with long arm cast ranged from 4 to 20 weeks, with an average of 6 weeks. This was followed by a short arm cast for the balance of treatment. In the fractures that failed to unite, the average time from injury to initiation of treatment was 50 months (range, 6 to 241 months). In the nonunions that healed, the average was 27 months (range, 6 to 170 months). Among fractures that were more than 60 months old, only 2 (29%) of 7 healed, while 30 (73%) of 41 fractures that were less than 60 months old healed. In the 37 patients with healed fractures, 35 returned to their pre-injury work. Eleven returned to heavy labor, 13 to moderately strenuous work, and 11 to light work. One patient who had performed heavy labor was not able to return to his previous occupation, and information was not available concerning one patient. At final follow-up, in patients with healed fractures, wrist extension averaged 78% of the opposite normal wrist and wrist flexion averaged 90%. Radial deviation averaged 79%, and ulnar deviation averaged 72%. Grip strength averaged 77% of the opposite normal hand. Individual patient reviews were done to evaluate contributing causes in the 17 failure cases. One patient had a synovial pseudoarthrosis, proved by arthrogram, and
912
The Journal of HAND SURGERY
Adams et at.
Table I. Characteristics
of study population Original patients (44)
Average time since injury (mo) Previous surgical procedures (%) Proximal pole avascular necrosis (%) Proximal one third nonunion (%) Initial long/short arm casting (%) Union rate (%)
Additional patienrs
I
40 22 19 18 60140 75
00) 20 16 25 25 50150 40
I
All 54 patients 35 21 20 20 58142 69
Comparison of factors that may have affected union rate. Three study groups are listed
three patients demonstrated carpal collapse. Four patients showed poor cooperation and removed their own casts or failed to perform the recommended number of hours of electrical stimulation. There were nine failures among the patients who conformed to the criteria for inclusion in this study. Although the union rate was much lower for the additional patients in this review, there were no identifiable factors in this group to separate them from the original 44 patients (Table I).
Discussion During the last three decades, electrical stimulation has received considerable attention for its effects on the musculoskeletal system. Although the mechanism by which electrical fields alter biologic processes has not been fully defined, clinical application has gained wide popularity with more than 50,000 patients treated with including 20,000 patients electrical stimulation,‘2 treated with PEMF16 since 1979. Although a large number of patients have been treated, relatively few clinical studies have attempted to evaluate the indications and results of electrical stimulation treatment. Many of these studies have involved only a small number of patients or have included several different bones and more than one electrical device. This study continuation of PEMF and casting for the treatment of scaphoid nonunion demonstrates a decreased success rate for healing since the last report from 80% to 69%” Beckenbaugh” reported an overall union rate of 67% for 24 patients treated with PEMF and casting. Other studies have reported healing rates ranging from 77% to 95%. However, they used various methods of electrical stimulation.3s 5*“9 I8 Anatomic location of the nonunion appears to influence treatment response. In this series, the proximal pole nonunions healed in 50% compared with 73% for middle and distal third nonunions. In a combined series in which more than one electrical stimulation method was used, Osterman and Bora’* reported healing in 64% of proximal pole nonunions and 84% of waist nonunions. The difference in the healing rates for the level of injury
is similar to that reported for bone-grafting procedures. ‘. ” However, treatment of a small proximal pole nonunion with a bone-grafting procedure, especially when signs of avascular changes are present, is technically demanding and often gives poor results. The importance of using rigid immobilization in a long arm thumb spica cast, at least for the initial period of treatment, has been shown in other series.“, ‘I The previous review showed a healing rate of 75% with short arm casting compared with 92% with long arm casting. In this review, long arm casting was associated with a 24% higher union rate. Beckenbaugh” reported healing rates of 58% for short arm casting versus 87% for long arm casting. Osterman and Bora” had a similar experience. Since these patients are often young, active males who can be difficult to treat with an extended period of casting, patient education and cooperation are important for a successful outcome with PEMF and casting. ‘* The results have again demonstrated that nonunions of more than 5 years duration are less likely to respond to PEMF treatment. However, the correlation is less prominent in this recent review. Osterman and Bora did not support this finding. They believe that patients who have long-standing nonunions without associated arthritis or carpal collapse are more likely to have a strong fibrous union. They claim these patients show a good response to PEMF treatment. Their patients with nonunions of long duration achieved an 80% healing rate. ” The longest duration of nonunion in Beckenbaugh’s series was only 4 years.” Previous surgery does not seem to adversely affect the results of electrical stimulation. Both in the previous review and in this review, the healing rate among patients with one or more previous operations was similar to the overall rate. Osterman and Bora had a similar experience when they used other electrical devices, with a 79% union rate in these patients.” Periscaphoid arthritis, fracture angulation and displacement, carpal instability, and synovial pseudarthrosis should be absent radiographically before PEMF
Vol. 17A, No. 5 September 1992
and cast treatment is considered. As with other treatment alematives, the presence of arthritis will preclude a good long-term result and is therefore a relative contraindication. Fracture angulation or displacement can be associated with carpal instability. Although healing of the nonunion may be achieved with this treatment method, a malunion will result and the instability will persist. Synovial pseudarthrosis is an absolute contraindication to electrical stimulation.“* I6 An arthrogram is required to prove the presence or absence of this condition, however, plain x-ray films are often highly suggestive if the pseudarthrosis is well established. A synovial pseudoarthrosis may have been undetected and responsible for some of our failures, since arthrograms were not routinely performed. Perhaps an arthrogram should be obtained in every patient with a scaphoid nonunion when the plan of care does not include open, operative treatment. The difficulty of interpreting the healing of a scaphoid nonunion during treatment is a universal problem. Overoptimism by the physician and the patient is probably common for all methods of treatment, because long-term cast immobilization becomes tedious. In the previous report, healing may have been inaccurately assessed in at least two patients. Although tomograms, CT scans, and magnetic resonance imaging may improve diagnostic accuracy, these studies are expensive and may not clearly define the healing status. Therefore, the healing rates reported for various scaphoid nonunion treatments are probably too high in most series. Radiographic evidence of avascular necrosis was once considered a contraindication to electrical stimulation.3 Although union continued to be achieved in patients with avascular necrosis, the union rate has decreased from 89% to 73% since the previous review. Osterman and Bora” reported a 66% union rate with electrical stimulation by other devices in the presence of avascular changes. Most authors believe bone grafting represents the standard for the treatment of the nonunited scaphaid. 1. 17.19.10 Electrical stimulation methods, including PEMF, have not achieved this degree of consistent success. However, future developments in the techniques of electrical stimulation may improve the results. The advantages of a noninvasive method of treatment over a bone-grafting procedure are evident. In addition, the length of treatment is similar to that with a bone-grafting operation. ‘. I’. 19.*OUnfortunately, the protocols of all electrical devices currently in use require or recommend simultaneous cast immobilization. To date, a study has not been performed to compare electrical stimulation and casting with casting alone for the treatment of scaphoid nonunion. Therefore, the skepticism regarding the efficacy of PEMF and other
Treatment of scaphoid nonunion
913
electrical devices is justified. From the results of this study, we believe that electrical stimulation by PEMF should be specifically considered as a treatment alternative when previous surgery has failed, for difficult proximal pole fractures, and whenever surgery is not safe or is rejected by the patient. Although these indications have not significantly changed, this review suggests that success with PEMF and casting is less likely than was previously reported. To further define indications, treatment protocol, and efficacy of PEMF, additional studies are needed. Optimally, this should be a prospective, randomized, and multicenter study that compares several alternative methods of treatment for scaphoid nonunion. Until more accurate information is available, we believe that a thorough discussion of treatment options with the patient is advisable. REFERENCES 1. Cooney W, Dobyns JH, Linscheid RL. Nonunion of the scaphoid: analysis of the results from bone grafting. J HAND SURG 1980;5:343-54. 2. Cooney W, Dobyns JH, Linscheid RL. Fractures of the scaphoid: a rational approach to management. Clin Orthop 1980;149:90-7. 3. Bora FW Jr, Osterman AL, Brighton CT. The electrical treatment of scaphoid nonunion. Clin Orthop 198 1;161: 30-8. 4. Bora FW Jr, Osterman AL, Woodbury DF, Brighton CT. Treatment of nonunion of the scaphoid by direct current. Orthop Clin North Am 1984;15:107-12. 5. Brighton CT. The semi-invasive method of treating nonunion with direct current. Orthop Clin North Am 1984;15:33-45. 6. Stewart MJ: Fractures of the carpal navicular (scaphoid): a report of 436 cases. J Bone Joint Surg 1954;36A:9981006. 7. Cosio MQ, Camp RA. Percutaneous pinning of symptomatic scaphoid nonunions. J HAND SURG 1986;llA: 350-5. 8. Patterson D. Treatment of nonunion with a constant direct current: a totally implantable system. Orthop Clin North Am 1984;15:47-59. 9. Basset CAL, Valdes MG, Hemandez E. Modification of fracture repair with selected pulsing electromagnetic field. J Bone Joint Surg 1982;64A:888-95. 10. Beckenbaugh RO. Noninvasive pulsed electromagnetic stimulation in the treatment of scaphoid nonunion. Orthop Trans 1985;9:444. Il. Frykman GK, Taleisnik J, Peters GA. et al. Treatment of nonunited scaphoid fractures by pulsed electromagnetic field and cast. J HAND SURG 1986;l lA:344-9. 12. Osterman AL, Bora FW Jr. Electrical stimulation applied to bone and nerve injuries in the upper extremity. Orthop Clin North Am 1986;17:353-64. 13. Amadio PC, Berquist TH, Smith DK, Ilstrup DM, Cooney WP, Linscheid RL. Scaphoid malunion. J HAND SURG 1989;14A:679-87.
The Journal of HAND SURGERY
Adams et al
14. Smith DK, An KN, Cooney WP, Linscheid RL, Chao EY. Effects of a scaphoid wrist osteotomy on carpal kinematics. J Orthop Res 1989;7:590-8. 15. Electra-Biology, Inc, Fairtield, NJ. Procedure manual for the prescribing, application, and management of the EBI Bi-Osteogen System 204, May, 1979. 16. Basset CAL. The development and application of pulsed electromagnetic fields (PEMFs) for ununited fractures and arthrodeses. Orthop Clin North Am 1984;15:61-87. 17. Russe 0. Fracture of the carpal navicular: diagnosis, nonoperative treatment and operative treatment. J Bone Joint Surg 1960;421\:759-68.
18. Heckman JD, Ingram AJ, Loyd RD, et al. Nonunion treatment with pulsed electromagnetic fields. Clin Orthop 1981;161:58-66. 19. Dooley BJ. Inlay bone grafting for non-union of the scaphoid bone by the anterior approach. J Bone Joint Surg 1968;5OB: 102-9. 20. Mulder JD. The results of 100 cases of pseudarthrosis in the scaphoid bone treated by the Matti-Russe operation. J Bone Joint Surg 1968:50B:llO-5.
Thumb interphalangeal joint sesamoiditis LTC Kenneth J. Edwards, Bethesda, hid.
T
here are several
reports
MC, USN, and LTC W. Andrew Eglseder,
MC, USNR,
in the medical
of chronic pain in the thumb due to problems of the sesamoid bones. ‘-3The sesamoids may become involved by rheumatoid arthritis or osteoarthritis,4 or they may be fractured.5 Usually these problems occur at the metacarpophalangeal (MP) joint. We have not found a report of a problem sesamoid at the interphalangeal (IP) joint. literature
Case report A 40-year-old female nursing supervisor, who was an avid recreational weight lifter, complained of 5 months of pain at the IP joint of her nondominant left thumb. She denied trauma
From the Department of Orthopaedic Surgery. National Naval Medical Center, Bethesda, Md. The opinions or assertions contained herein are those of the authors and are not to be construed as official or as reflecting the views of the Department of the Navy or the Department of Defense. Received for publication April 5, 1990; accepted in revised form May 22, 1991. No benefits in any form have been received or will be received from a commercial this article.
party related directly or indirectly
to the subject of
Reprint requests: W. Andrew Eglseder, MD, Department of Orthopaedic Surgery, University of Maryland Hospitals, 22 S. Greene St., Baltimore, MD 21201. 3/l/31694
914
Fig. 1. Technetium bone scan demonstrating increased activity in the region of the interphalangeal joint of the left thumb.
to the thumb. Initially, resting her hand decreased the symptoms, but at presentation her pain was constant. Neither nonsteroidal anti-inflammatory drugs nor splinting relieved the pain. A corticosteroid injection into the tender area gave brief pain relief. A technetium bone scan showed increased uptake at the thumb IP joint (Fig. 1). Although a plain x-ray film was normal, tomograms were interpreted as showing a narrowed subsesamoid joint. At surgery there was degeneration
fields (PEMF) and cast immobilization.
overall success rate for healing has decreased Proximal
pole fractures
evidence of avascular
healed in 50%.
Fifty-four patients were reviewed. The
since the previous review from 80% to 69%.
Success in nonunions
with associated
radiographic
necrosis decreased from 89% to 73%. Although we believe that the in-
dications for use of PEMF have not changed significantly, this study suggests that a successful outcome with PEMF and casting is less likely than previously reported. We believe that until additional clinical studies have further defined the indications, treatment protocol, and efficacy of this method PEMF treatment should be a secondary alternative to bone-grafting procedures. (J HAND SURG 1992;17A:910-4.)
Brian D. Adams, MD, Burlington, Vt., Gary K. Frykman, MD, Loma Linda, Calif., and Julio Taleisnik, MD, Orange, Calif.
N onunited
scaphoids have been managed by numerous methods during the past three decades. Although a displaced scaphoid fracture or a nonunion associated with carpal instability is best managed with open reduction and bone grafting,” 2 uncomplicated nonunion has been successfully treated with electrical stimulation.3-5 Treatment with electrical stimulation is highly controversial, however. This method has not been shown to be consistently better than other nonoperative methods.6, ’ In addition, further skepticism is caused by a poor understanding of the biologic mechanisms of electrically induced osteogenesis. Despite the lack of controlled experimental studies to substantiate the efficacy, electrical stimulation has been used clinically for the treatment of scaphoid nonunion.
From the Department of Orthopaedics and Rehabilitation, University of Vermont, Burlington, Vt., and the Department of Orthopedic Surgery, Loma Linda University School of Medicine, Loma Linda, Calif. Received for publication Jan. 20, 1992.
May 31, 1991; accepted
in revised form
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: Brian D. Adams, MD, Department of Orthopaedics and Rehabilitation, University of Vermont, Burlington, VT 05405. 311136951
910
Early methods of electrical stimulation required invasive procedures53 ’ and therefore offered few advantages over a bone-grafting procedure. With the introduction of the pulsed electromagnetic field (PEMF) with external coils, the advantages of a noninvasive technique that can be applied in the office were apparent.’ However, only a few studies have reported the results of PEMF treatment for scaphoid nonunion.“.” This article presents a continuation of a cIinicaI study of the treatment of scaphoid nonunion with PEMF and casting. Clinical and anatomic findings that may affect the union rate were evaluated. Materials
and methods
We reviewed all cases of scaphoid nonunion treated with PEMF and casting from 1979 to 1989. This represents the combined material of the previous study” and additional cases treated since that report. Because radiographic interpretation of the healing scaphoid can be difficult, further follow-up of available patients from the previous study was performed to assess the status of their supposed union. To be included in this study, the scaphoid fracture had to be at least 6 months old and a standardized protocol of treatment had to be followed. Regardless of previous treatment methods, no operation had been performed during or just before initiation of PEMF treatment. None of the patients had displacement or
Vol. 17A, No. 5 September 1992
significant angulation at the nonunion site, and none showed arthritis of the periscaphoid joints. Three patients reported in the previous series showed loss of carpal alignment, with a dorsal intercalated segment instability pattern before treatment. Since the outcome of treatment in these patients was poor, it was concluded that carpal instability associated with a scaphoid fracture is a contraindication to PEMF and casting alone. This is in agreement with other reports describing the treatment of scaphoid fractures complicated by carpal instability. ‘, 13.I4 Except for the exclusion of patients with carpal instability, there was no change in the inclusion criteria. In the present study a series of consecutive cases were treated by the recommended product protoco1.‘5 External PEMF coils were centered over the scaphoid and attached to either a long arm thumb spica cast or a short arm thumb spica cast. To be included in the final analysis, all patients had to be treated either until the fracture healed or for at least a 3-month period. Sixty-two patients were initially treated. Three patients failed to return for follow-up examination after discontinuation of PEMF treatment. Although their fractures had healed, these patients were excluded from the final analysis. Five additional patients were excluded from the study because they received inadequate treatment of 2 months or less of electrical stimulation. The remaining 54 patients were treated according to the protocol and were available for review. This represents the 44 patients reported previously and 10 additional patients, with further follow-up on 11 of the first 44 patients. There were 51 males and 3 females with an average of 26 years (range, 14 to 46 years). The nonunion site was in the proximal third in 10 patients, in the middle third in 41, and in the distal third in 3 patients. Ten patients had had one previous bone-graft operation, and two patients had undergone two previous operations before initiation of PEMF and casting. Eleven patients showed radiographic evidence of avascular changes in the proximal fragment. The average time from injury to treatment was 35 months, with a range of 6 to 241 months. All patients who were included in the final review were examined from 1 to 33 months after the treatment was stopped, for an average follow-up of 8’/2 months. Plain radiographic evaluation was the standard method used for the initial assessment of nonunion as well as for the final determination of healing status. Anteroposterior, lateral, and scaphoid views were available for each case. Although tomograms and arthrograms were obtained in some cases, these studies were not used for the initial and final assessments in this review.
Treatment of scaphoid nonunion
911
Results The nonunions healed in 37 (69%) of the 54 patients. Five (50%) of the ten nonunions in the proximal third healed, and 32 (73%) of the 44 nonunions in the middle and distal thirds healed. In those patients with evidence of avascular changes of the proximal fragment before PEMF and casting treatment, eight of eleven (73%) nonunions healed. Eight of 12 patients who had undergone previous bone-grafting operations healed. Of the 11 patients who had been followed up since the last report, two were found to have x-ray evidence of nonunion that had been previously interpreted as healed. Thus either a refracture had occurred or an inaccurate assessment of fracture healing had been made. These patients were included in the failed group for the present analysis; this changed the healing rate in the original 44 patients from 80% to 75%. Only four of the ten additional patients achieved union. For the patients in whom nonunion healed, the average duration of electrical stimulation was 4 months, with a range of 2.5 to 9 months. Four patients had PEMF and casting for more than 6 months. In five patients records did not indicate whether an above-elbow or a below-elbow cast was used. In the remaining 49 patients, healing occurred in 24 (83%) of the 29 who were treated with a long arm thumb spica cast and in 13 (59%) of the 22 who were treated with a short arm thumb spica cast. The duration of immobilization with long arm cast ranged from 4 to 20 weeks, with an average of 6 weeks. This was followed by a short arm cast for the balance of treatment. In the fractures that failed to unite, the average time from injury to initiation of treatment was 50 months (range, 6 to 241 months). In the nonunions that healed, the average was 27 months (range, 6 to 170 months). Among fractures that were more than 60 months old, only 2 (29%) of 7 healed, while 30 (73%) of 41 fractures that were less than 60 months old healed. In the 37 patients with healed fractures, 35 returned to their pre-injury work. Eleven returned to heavy labor, 13 to moderately strenuous work, and 11 to light work. One patient who had performed heavy labor was not able to return to his previous occupation, and information was not available concerning one patient. At final follow-up, in patients with healed fractures, wrist extension averaged 78% of the opposite normal wrist and wrist flexion averaged 90%. Radial deviation averaged 79%, and ulnar deviation averaged 72%. Grip strength averaged 77% of the opposite normal hand. Individual patient reviews were done to evaluate contributing causes in the 17 failure cases. One patient had a synovial pseudoarthrosis, proved by arthrogram, and
912
The Journal of HAND SURGERY
Adams et at.
Table I. Characteristics
of study population Original patients (44)
Average time since injury (mo) Previous surgical procedures (%) Proximal pole avascular necrosis (%) Proximal one third nonunion (%) Initial long/short arm casting (%) Union rate (%)
Additional patienrs
I
40 22 19 18 60140 75
00) 20 16 25 25 50150 40
I
All 54 patients 35 21 20 20 58142 69
Comparison of factors that may have affected union rate. Three study groups are listed
three patients demonstrated carpal collapse. Four patients showed poor cooperation and removed their own casts or failed to perform the recommended number of hours of electrical stimulation. There were nine failures among the patients who conformed to the criteria for inclusion in this study. Although the union rate was much lower for the additional patients in this review, there were no identifiable factors in this group to separate them from the original 44 patients (Table I).
Discussion During the last three decades, electrical stimulation has received considerable attention for its effects on the musculoskeletal system. Although the mechanism by which electrical fields alter biologic processes has not been fully defined, clinical application has gained wide popularity with more than 50,000 patients treated with including 20,000 patients electrical stimulation,‘2 treated with PEMF16 since 1979. Although a large number of patients have been treated, relatively few clinical studies have attempted to evaluate the indications and results of electrical stimulation treatment. Many of these studies have involved only a small number of patients or have included several different bones and more than one electrical device. This study continuation of PEMF and casting for the treatment of scaphoid nonunion demonstrates a decreased success rate for healing since the last report from 80% to 69%” Beckenbaugh” reported an overall union rate of 67% for 24 patients treated with PEMF and casting. Other studies have reported healing rates ranging from 77% to 95%. However, they used various methods of electrical stimulation.3s 5*“9 I8 Anatomic location of the nonunion appears to influence treatment response. In this series, the proximal pole nonunions healed in 50% compared with 73% for middle and distal third nonunions. In a combined series in which more than one electrical stimulation method was used, Osterman and Bora’* reported healing in 64% of proximal pole nonunions and 84% of waist nonunions. The difference in the healing rates for the level of injury
is similar to that reported for bone-grafting procedures. ‘. ” However, treatment of a small proximal pole nonunion with a bone-grafting procedure, especially when signs of avascular changes are present, is technically demanding and often gives poor results. The importance of using rigid immobilization in a long arm thumb spica cast, at least for the initial period of treatment, has been shown in other series.“, ‘I The previous review showed a healing rate of 75% with short arm casting compared with 92% with long arm casting. In this review, long arm casting was associated with a 24% higher union rate. Beckenbaugh” reported healing rates of 58% for short arm casting versus 87% for long arm casting. Osterman and Bora” had a similar experience. Since these patients are often young, active males who can be difficult to treat with an extended period of casting, patient education and cooperation are important for a successful outcome with PEMF and casting. ‘* The results have again demonstrated that nonunions of more than 5 years duration are less likely to respond to PEMF treatment. However, the correlation is less prominent in this recent review. Osterman and Bora did not support this finding. They believe that patients who have long-standing nonunions without associated arthritis or carpal collapse are more likely to have a strong fibrous union. They claim these patients show a good response to PEMF treatment. Their patients with nonunions of long duration achieved an 80% healing rate. ” The longest duration of nonunion in Beckenbaugh’s series was only 4 years.” Previous surgery does not seem to adversely affect the results of electrical stimulation. Both in the previous review and in this review, the healing rate among patients with one or more previous operations was similar to the overall rate. Osterman and Bora had a similar experience when they used other electrical devices, with a 79% union rate in these patients.” Periscaphoid arthritis, fracture angulation and displacement, carpal instability, and synovial pseudarthrosis should be absent radiographically before PEMF
Vol. 17A, No. 5 September 1992
and cast treatment is considered. As with other treatment alematives, the presence of arthritis will preclude a good long-term result and is therefore a relative contraindication. Fracture angulation or displacement can be associated with carpal instability. Although healing of the nonunion may be achieved with this treatment method, a malunion will result and the instability will persist. Synovial pseudarthrosis is an absolute contraindication to electrical stimulation.“* I6 An arthrogram is required to prove the presence or absence of this condition, however, plain x-ray films are often highly suggestive if the pseudarthrosis is well established. A synovial pseudoarthrosis may have been undetected and responsible for some of our failures, since arthrograms were not routinely performed. Perhaps an arthrogram should be obtained in every patient with a scaphoid nonunion when the plan of care does not include open, operative treatment. The difficulty of interpreting the healing of a scaphoid nonunion during treatment is a universal problem. Overoptimism by the physician and the patient is probably common for all methods of treatment, because long-term cast immobilization becomes tedious. In the previous report, healing may have been inaccurately assessed in at least two patients. Although tomograms, CT scans, and magnetic resonance imaging may improve diagnostic accuracy, these studies are expensive and may not clearly define the healing status. Therefore, the healing rates reported for various scaphoid nonunion treatments are probably too high in most series. Radiographic evidence of avascular necrosis was once considered a contraindication to electrical stimulation.3 Although union continued to be achieved in patients with avascular necrosis, the union rate has decreased from 89% to 73% since the previous review. Osterman and Bora” reported a 66% union rate with electrical stimulation by other devices in the presence of avascular changes. Most authors believe bone grafting represents the standard for the treatment of the nonunited scaphaid. 1. 17.19.10 Electrical stimulation methods, including PEMF, have not achieved this degree of consistent success. However, future developments in the techniques of electrical stimulation may improve the results. The advantages of a noninvasive method of treatment over a bone-grafting procedure are evident. In addition, the length of treatment is similar to that with a bone-grafting operation. ‘. I’. 19.*OUnfortunately, the protocols of all electrical devices currently in use require or recommend simultaneous cast immobilization. To date, a study has not been performed to compare electrical stimulation and casting with casting alone for the treatment of scaphoid nonunion. Therefore, the skepticism regarding the efficacy of PEMF and other
Treatment of scaphoid nonunion
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electrical devices is justified. From the results of this study, we believe that electrical stimulation by PEMF should be specifically considered as a treatment alternative when previous surgery has failed, for difficult proximal pole fractures, and whenever surgery is not safe or is rejected by the patient. Although these indications have not significantly changed, this review suggests that success with PEMF and casting is less likely than was previously reported. To further define indications, treatment protocol, and efficacy of PEMF, additional studies are needed. Optimally, this should be a prospective, randomized, and multicenter study that compares several alternative methods of treatment for scaphoid nonunion. Until more accurate information is available, we believe that a thorough discussion of treatment options with the patient is advisable. REFERENCES 1. Cooney W, Dobyns JH, Linscheid RL. Nonunion of the scaphoid: analysis of the results from bone grafting. J HAND SURG 1980;5:343-54. 2. Cooney W, Dobyns JH, Linscheid RL. Fractures of the scaphoid: a rational approach to management. Clin Orthop 1980;149:90-7. 3. Bora FW Jr, Osterman AL, Brighton CT. The electrical treatment of scaphoid nonunion. Clin Orthop 198 1;161: 30-8. 4. Bora FW Jr, Osterman AL, Woodbury DF, Brighton CT. Treatment of nonunion of the scaphoid by direct current. Orthop Clin North Am 1984;15:107-12. 5. Brighton CT. The semi-invasive method of treating nonunion with direct current. Orthop Clin North Am 1984;15:33-45. 6. Stewart MJ: Fractures of the carpal navicular (scaphoid): a report of 436 cases. J Bone Joint Surg 1954;36A:9981006. 7. Cosio MQ, Camp RA. Percutaneous pinning of symptomatic scaphoid nonunions. J HAND SURG 1986;llA: 350-5. 8. Patterson D. Treatment of nonunion with a constant direct current: a totally implantable system. Orthop Clin North Am 1984;15:47-59. 9. Basset CAL, Valdes MG, Hemandez E. Modification of fracture repair with selected pulsing electromagnetic field. J Bone Joint Surg 1982;64A:888-95. 10. Beckenbaugh RO. Noninvasive pulsed electromagnetic stimulation in the treatment of scaphoid nonunion. Orthop Trans 1985;9:444. Il. Frykman GK, Taleisnik J, Peters GA. et al. Treatment of nonunited scaphoid fractures by pulsed electromagnetic field and cast. J HAND SURG 1986;l lA:344-9. 12. Osterman AL, Bora FW Jr. Electrical stimulation applied to bone and nerve injuries in the upper extremity. Orthop Clin North Am 1986;17:353-64. 13. Amadio PC, Berquist TH, Smith DK, Ilstrup DM, Cooney WP, Linscheid RL. Scaphoid malunion. J HAND SURG 1989;14A:679-87.
The Journal of HAND SURGERY
Adams et al
14. Smith DK, An KN, Cooney WP, Linscheid RL, Chao EY. Effects of a scaphoid wrist osteotomy on carpal kinematics. J Orthop Res 1989;7:590-8. 15. Electra-Biology, Inc, Fairtield, NJ. Procedure manual for the prescribing, application, and management of the EBI Bi-Osteogen System 204, May, 1979. 16. Basset CAL. The development and application of pulsed electromagnetic fields (PEMFs) for ununited fractures and arthrodeses. Orthop Clin North Am 1984;15:61-87. 17. Russe 0. Fracture of the carpal navicular: diagnosis, nonoperative treatment and operative treatment. J Bone Joint Surg 1960;421\:759-68.
18. Heckman JD, Ingram AJ, Loyd RD, et al. Nonunion treatment with pulsed electromagnetic fields. Clin Orthop 1981;161:58-66. 19. Dooley BJ. Inlay bone grafting for non-union of the scaphoid bone by the anterior approach. J Bone Joint Surg 1968;5OB: 102-9. 20. Mulder JD. The results of 100 cases of pseudarthrosis in the scaphoid bone treated by the Matti-Russe operation. J Bone Joint Surg 1968:50B:llO-5.
Thumb interphalangeal joint sesamoiditis LTC Kenneth J. Edwards, Bethesda, hid.
T
here are several
reports
MC, USN, and LTC W. Andrew Eglseder,
MC, USNR,
in the medical
of chronic pain in the thumb due to problems of the sesamoid bones. ‘-3The sesamoids may become involved by rheumatoid arthritis or osteoarthritis,4 or they may be fractured.5 Usually these problems occur at the metacarpophalangeal (MP) joint. We have not found a report of a problem sesamoid at the interphalangeal (IP) joint. literature
Case report A 40-year-old female nursing supervisor, who was an avid recreational weight lifter, complained of 5 months of pain at the IP joint of her nondominant left thumb. She denied trauma
From the Department of Orthopaedic Surgery. National Naval Medical Center, Bethesda, Md. The opinions or assertions contained herein are those of the authors and are not to be construed as official or as reflecting the views of the Department of the Navy or the Department of Defense. Received for publication April 5, 1990; accepted in revised form May 22, 1991. No benefits in any form have been received or will be received from a commercial this article.
party related directly or indirectly
to the subject of
Reprint requests: W. Andrew Eglseder, MD, Department of Orthopaedic Surgery, University of Maryland Hospitals, 22 S. Greene St., Baltimore, MD 21201. 3/l/31694
914
Fig. 1. Technetium bone scan demonstrating increased activity in the region of the interphalangeal joint of the left thumb.
to the thumb. Initially, resting her hand decreased the symptoms, but at presentation her pain was constant. Neither nonsteroidal anti-inflammatory drugs nor splinting relieved the pain. A corticosteroid injection into the tender area gave brief pain relief. A technetium bone scan showed increased uptake at the thumb IP joint (Fig. 1). Although a plain x-ray film was normal, tomograms were interpreted as showing a narrowed subsesamoid joint. At surgery there was degeneration