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The Journal of Bone and Joint Surgery (American). 2005;87:468-474. doi:10.2106/JBJS.D.02807 © 2005 The Journal of Bone and Joint Surgery, Inc. What's New in Hand Surgery1 Mayo Clinic, 200 First Street S.W., Rochester, MN 55905. E-mail address: amadio.peter{at}mayo.edu
Specialty Update has been developed in collaboration with the Council of
Musculoskeletal Specialty Societies (COMSS) of the American Academy of
Orthopaedic Surgeons.
This update reviews material presented at the 2004 annual meetings of the American Society for Surgery of the Hand (ASSH), the American Association for Hand Surgery (AAHS), and the American Academy of Orthopaedic Surgeons (AAOS) as well as articles published in the field of hand surgery (other than those published in this journal) between August 2003 and July 2004. Meeting abstracts for the ASSH and AAOS annual meetings are maintained online at www.hand-surgery.org and www.aaos.org, respectively.
The treatment of traumatic injuries continues to be a principal preoccupation of hand surgeons. In one study reported to the AAHS, the importance of recognizing small palmar marginal fractures of the distal part of the radius was emphasized. This variant of the Barton fracture has a special propensity to result in late palmar subluxation of the wrist. Treatment with a palmar buttress plate is recommended but, because the fracture is very distal, accurate plate fixation that truly supports the fracture (and not the area proximal to the fracture) is essential if late subluxation is to be avoided.
Distal Radial Fractures With this in mind, it is interesting to review the major literature on distal radial fracture implants as reported in 2004. The treatment of distal radial fractures through a palmar approach with use of a plate and locking screws is becoming increasingly popular. In a presentation to the ASSH, a principal developer of such a device reported excellent results for forty-eight patients who had been followed for a minimum of one year. There was no comparison group. In a related retrospective study, the same investigator reported on a series of twenty-three patients with an age of more than seventy-five years who had been treated with the same device1. Postoperative rehabilitation included immediate finger exercises, early use of the hand, and splinting for an average of three weeks. After an averae duration of follow-up of sixty-three weeks, the mean volar tilt was 6°, the mean radial tilt was 20°, and the mean radial shortening was <1 mm. The mean final range of motion of the wrist included 58° of extension, 55° of flexion, 80° of pronation, and 76° of supination. The grip strength on the involved side was 77% of that on the contralateral side. There were no instances of plate failure or substantial loss of reduction. This same investigator reported to the AAHS on another, intramedullary, fixed-angle device that was used to treat distal radial fractures. After a mean duration of follow-up of six months, excellent results were reported for twenty patients who had been managed with this newer device. In a case series that was presented to the AAOS, excellent results were reported in association with an alternative strategy of fragment-specific fixation of distal radial fractures with use of a variety of small plates and pins. The investigator was not associated with the device being studied. Again, there was no comparison group. In a second paper that was presented to the AAOS, the complications of internal fixation of distal radial fractures were reviewed. Consistent with the findings of other studies, the Synthes dorsal pi plate was noted to be associated with the highest rate of complications. That device was associated with a 47% rate of reoperation, which was often necessary for the treatment of tendon irritation on the edges of the plate. In the study by Ikeda et al., eighteen patients with Colles fractures who had a mean age of seventy years (range, fifty-five to ninety-one years) were managed with intramedullary bone cementing2. The best indication for this technique was an unstable extra-articular Colles fracture associated with osteoporosis. Bone cement was packed into the void that was created by curettage of intramedullary cancellous bone from the dorsal fracture site. Intramedullary cementing caused little bleeding from the medullary canal and no irritation of the extensor tendons. With the resulting rigid fixation, patients were able to use the affected hand for light activities without any external orthosis the day after surgery. Cortical healing was seen in all patients within three months, and there had been no instances of cement loosening or other complications after a mean duration of follow-up of twenty-eight months (range, six to forty-three months). In a study by Leung et al., the stability of palmar plate fixation with use of a locking compression T-plate was compared with the stability of fixation with use of a conventional palmar T-plate and a dorsal T-plate in a cadaveric model of AO type-C2 fractures of the distal part of the radius3. The wrist axial load transmission through the radius was tested for each type of fixation. The results showed that, under 100 N of axial load, the palmar locking compression T-plate was superior to conventional palmar or dorsal T-plates and that it restored stability to a level comparable with that of the intact radius.
Carpal Tunnel Injuries When considering four-corner arthrodesis, the hand surgeon has many options. This procedure traditionally has been performed with use of pins or staples, but screws or circular plates have been used more recently. While circular plates have attracted recent interest, there have been few publications on the clinical results associated with these devices. The complications of four-corner arthrodesis were reviewed in a report on sixty-six patients that was presented to the ASSH. Thirty patients had been treated with a circular plate, and the other thirty-six had been treated with a mixture of pins, staples, or screws. After a mean duration of follow-up of thirty-three months, the nonunion rate was 26% for the group that had been managed with a circular plate and 3% for the group that had been managed with other methods. Even among patients with union, those who had been managed with a circular plate were more likely to complain of residual pain, to be dissatisfied with the result, and to require permanent work restrictions.
Scaphoid Fractures
As discussed in previous editions of this review, hand transplantation has remained a topic of great interest to hand surgeons. Limb allograft research was highlighted in a series of papers that were presented to the AAHS. The use of anti-CD40 antibody and partial T-cell depletion has resulted in prolonged acceptance of limb allografts in mice, even in the absence of immunosuppressive drugs, and the use of short-term cyclosporin and T-cell receptor antibodies has resulted in similar outcomes in rats. On the basis of these animal studies as well as on anecdotal evidence related to hand transplantation patients who stopped taking their immunosuppressive medications for a time, stable chimerism seems to be a potentially achievable goal for patients with limb transplantation. If temporary immunosuppression could indeed induce a stable, drug-free tolerance for the transplanted limb, then limb transplantation would become a more attractive option because temporary immunosuppression would avoid the need for, and complications related to, prolonged immunosuppressive therapy. While these reports have generated optimism on the immunology front, it is unlikely that the level of function following hand transplantation will ever exceed that following hand replantation. The long-term function following hand replantation was evaluated in a recent study of eight adults5. Despite fairly good motor recovery, the replanted hands had poor sensory recovery and severe cold intolerance. Measurable two-point discrimination in the injured hand was noted only in patients who were less than forty years old. These data suggest that hand replantation and transplantation may have a greater place in the treatment of younger patients and that an age of more than forty years may be a relative contraindication when considering these procedures.
Flexor tendon injuries in the finger continue to represent a challenge for hand surgeons. Groth, in a very interesting article, proposed a logical, eight-step graded-resistance therapy program for rehabilitation after flexor tendon injury that was based on current information on the strength of tendon repairs in vitro and the magnitude of tendon forces in vivo6. A study by Lattanza et al. that was presented to the ASSH has added further to that knowledge base. In the study by Lattanza et al., tendon forces were monitored during open carpal tunnel release and were compared with the strength of tendon repair. The findings confirmed that passive place and active hold exercises can be used safely in the early phases of tendon rehabilitation. In another very interesting paper that was presented to the ASSH, the concept of chemoprotection of tendon repairs with use of botulinum toxin was investigated in a rat model. In that study, Achilles tendons were repaired and then the gastrocnemius muscle was injected with botulinum toxin. All of the repairs ruptured in the control group, whereas none did so in the treatment group.
Nerve injuries also continue to be a challenge for hand surgeons. It is rare for adults to recover normal sensibility after nerve repair. In an effort to improve rehabilitation after nerve repair, the authors of a paper that was presented to the ASSH studied the use of "sensory bypass," in which auditory feedback from microphones in special gloves was used to amplify friction sounds of contact with objects. This feedback was then used early in the rehabilitation period for ten patients, each of whom had better final sensory recovery than did comparable patients who had been managed with standard sensory reeducation. The findings of that study suggest that the quality of sensory recovery after nerve repair is strongly influenced by the quality of the rehabilitation and is not solely determined by the technical factors of the injury and its repair. A related case report was published recently7.
Osteonecrosis affects several carpal bones. Osteonecrosis of the carpal scaphoid (Preiser's disease) is uncommon and difficult to treat. A paper presented to the AAHS described eight patients with Preiser's disease who were managed with a vascularized bone graft from the distal part of the radius. Pain was reduced in all patients, but the graft was unsuccessful in revascularizing the proximal pole. In an interesting paper that was presented to the ASSH, the use of vascularized bone grafts for the treatment of scaphoid nonunion also was noted to have limitations. A review of fifty-two such nonunions revealed poorer union rates in association with factors such as smoking (nonunion rate, 46%) and osteonecrosis of the proximal pole (nonunion rate, 50%). Graft-related complications, including graft extrusion and resorption, were noted in five patients. Osteonecrosis of the lunate (Kienbock disease) also can be treated with vascularized bone grafts, but such treatment has limitations similar to those described above in association with osteonecrosis of the scaphoid. A novel tissue-engineering approach was the focus of a laboratory study that was presented to the ASSH. In that study, scaffolds of hyaluronic acid and collagen were seeded with autologous stem cells in a rabbit model of Kienbock disease. A neolunate had formed by twelve weeks, but its function in situ was not reported.
The treatment of wrist arthritis is another controversial topic for hand surgeons. The role of proximal row carpectomy was discussed in a paper that was presented to the ASSH. In that study, eighteen of twenty-two patients who had been managed with proximal row carpectomy had had no further surgery after a minimum duration of follow-up of ten years. Fourteen patients were very satisfied with the long-term result, one-half of the patients were pain-free, and the average grip strength was 91% of that on the contralateral side. While 80% of the patients had degenerative changes in the wrist at the time of the final radiographic assessment, the radiographic changes did not correlate with symptoms or function. Another alternative, wrist arthroplasty, continues to improve. Rizzo and Beckenbaugh, in a retrospective review of the results of seventeen Biaxial total wrist arthroplasties (DePuy Orthopedics, Warsaw, Indiana) that had been performed with use of a long-stem metacarpal component between 1993 and 1997, reported marked improvement in terms of both pain and grip strength8. All patients were satisfied with the result. While four patients showed radiographic evidence of radiolucency about the cement mantle, there was no gross loosening or settling and no patient required revision surgery. Despite these excellent results, however, this implant was recently removed from the market by its manufacturer. The third surgical alternative for the treatment of wrist arthritis is arthrodesis. Murphy et al. recently compared the results of arthrodesis with those of arthroplasty in a study of two matched cohorts of patients who had rheumatoid arthritis of the wrist9. The outcome measures included the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire; the Patient-Rated Wrist Evaluation (PRWE) questionnaire; and a review of surgical complications. A total of forty-six patients with fifty-one wrists (twenty-four of which had been treated with arthrodesis and twenty-seven of which had been treated with arthroplasty) were reviewed retrospectively after one to five years of follow-up. The wrist arthroplasties were performed with the Universal implant (KMI, San Diego, California), and the arthrodeses were performed with a plate technique. There were no significant differences between the two groups with regard to the survey scores, although patients in the arthroplasty group did show a trend toward greater ease with personal hygiene and fastening buttons. The complication rates for the two groups were also similar (56% and 52% for the arthrodesis and arthroplasty groups, respectively). Thus, while arthroplasty continues to improve, its functional results are still in many cases similar to those of arthrodesis.
Arthritis at the base of the thumb is very common. This condition is often treated with excision of the trapezium followed by insertion of a rolled-up palmaris longus tendon, or "anchovy," into the trapeziectomy defect and capsular reconstruction. In a prospective study that was presented to the ASSH, 183 patients were randomized to one of three variations of this procedure: (1) trapeziectomy alone, (2) trapeziectomy with palmaris longus interposition, or (3) trapeziectomy with palmaris longus interposition and ligamentous reconstruction. All patients had supplemental Kirschner-wire fixation of the trapeziectomy defect for four weeks postoperatively. At one year, there was no difference in outcome among the three groups. In a recent study that was presented to the AAHS, the results of arthroscopic partial trapeziectomy were reported for twenty-three patients who had been followed for a minimum of five years. The results were not nearly as good as those associated with the traditional method; in the arthroscopy group, one-third of the patients needed a second operation. This finding was attributed to the use of Gore-Tex or allograft tendon for the interposition. The rate of success was greater among patients in whom the palmaris longus was used. Not all patients with trapeziometacarpal arthritis need surgery. The effectiveness of a single steroid injection and three weeks of splinting was examined in a prospective study of thirty patients who had a minimum of eighteen months of follow-up10. Thirteen patients had a reduction in the intensity of pain at six weeks, and twelve of these thirteen continued to have relief at the time of the final follow-up. Patients with mild disease were most likely to have improvement. Symptomatic isolated scaphotrapeziotrapezoid joint arthritis affects approximately 10% of the population. The results of arthroscopic débridement of this joint were evaluated in a study of ten consecutive patients11. A good or excellent subjective result was achieved in nine patients at the time of the final review, at an average of thirty-six months after surgery.
Surgery for arthritic finger joints continues to be a challenge for hand surgeons. Arthroplasty of the proximal interphalangeal joint was the subject of a report to the AAHS. Even after a very short maximum duration of follow-up of one year, five of thirty patients who had been managed with a new pyrolytic carbon implant required a reoperation, most often for instability. The long-term results of over 1800 metacarpophalangeal joint replacements that had been performed with use of silicone implants for the treatment of rheumatoid arthritis in 621 patients were presented to the ASSH. The rate of implant survival was 70% at fifteen years. Factors that were associated with survival included the performance of crossed intrinsic transfer and wrist realignment at the time of the arthroplasty. Factors that were not associated with survival included implant fracture (two-thirds of surviving implants were broken) and the use of grommets. A factor that was associated with failure was the need for concomitant proximal interphalangeal joint surgery. In a paper that was presented to the AAOS, a similar implant survival rate was noted in a group of patients who had received more than 200 silicone metacarpophalangeal joint implants. Outcomes analysis showed that only 40% of the patients were satisfied with the resulting hand function.
Hand reconstruction for the treatment of scleroderma is challenging. In a paper that was presented to the AAOS, excellent results were noted for eighty patients who had been managed with a two-stage reconstruction for the treatment of severe finger joint contractures. The first stage involved interphalangeal joint arthrodesis with shortening to avoid skin tension, and the second stage involved metacarpophalangeal joint arthroplasty with use of silicone implants. In a paper that was presented to the ASSH, the results of digital sympathectomy were reviewed for seventeen patients (ninety-five affected digits) after two to eight years of follow-up. All twenty-two ulcers healed, and sixteen of the seventeen patients had a decrease in pain. Trigger finger is a common problem. In a study that was presented to the ASSH, 528 fingers were treated with one or more injections of triamcinolone. The results were impressive: >60% of the fingers were cured after one injection and the overall cure rate was 90%. Only twelve fingers that had more than three injections were cured, supporting a "three strikes" rule before surgery is considered.
Wrist arthroscopy is increasingly being used to treat dorsal carpal ganglia. In a prospective, randomized study of seventy-two patients that was presented to the ASSH, similar results were noted in association with open and arthroscopic methods. Good results also were noted in a case series of forty-one patients who had been managed with the arthroscopic procedure, with only two recurrences requiring open excision12. Palmar wrist ganglia also are usually treated surgically, but this approach was called into question in a recent study. In a prospective cohort study of 182 patients who were followed for two to five years, Dias and Buch reported little difference in outcome between patients who had been managed with excision, those who had been managed with aspiration, and those who had received no treatment13. No significant difference was observed with regard to the rate of recurrence, which was reported to be 42% after excision and 47% after aspiration. Half of the untreated ganglia disappeared spontaneously. Eighty-five percent of the patients were satisfied regardless of treatment. Patients who had been managed with surgery had a complication rate of 20% and took more time off from work (fourteen days), whereas more patients in the untreated group thought that the persistent ganglion was unsightly.
Probably the largest demographic issue facing hand surgeons in 2004 is the declining number of hand fellows, with the number of available fellowships exceeding the number of applicants for the past few years. In an interesting survey that was presented to the ASSH, mentorship by a hand surgeon during residency was found to be the strongest motivating factor, whereas the lifestyle of hand surgeons, which includes substantial emergency care, was seen as a lesser detractor. Hand surgeons were encouraged to identify and to mentor promising residents early on so that there will be sufficient numbers of hand surgeons in the future. The Sixtieth Annual Meeting of the American Society for Surgery of the Hand will be held in San Antonio, Texas, on September 22, 23, and 24, 2005. For the first time in several years, this meeting will be held as a joint meeting with the American Society of Hand Therapists (www.asht.org). As usual, the ASSH is also offering a variety of continuing medical education (CME) programs throughout the year, including a program on hand trauma, to be held on May 6 and 7, in San Francisco, California, and a comprehensive hand surgery review course, to be held on July 15, 16, and 17, 2005, in Chicago, Illinois. The Thirty-sixth Annual Meeting of the American Association for Hand Surgery will be held on January 11 through 14, 2006, in Tucson, Arizona. The annual meeting of the AAHS is always held in combination with the annual meetings of the American Society for Reconstructive Microsurgery and the American Society for Peripheral Nerve. These three organizations also share certain management functions, permitting closer integration of their meetings, and even offer a combined registration option. Besides working together on courses of mutual interest, the two American hand surgery organizations also interact with other specialty societies. The American Society for Surgery of the Hand will hold a combined meeting with the Japanese Society for Surgery of the Hand, to be held on March 19 through 22, 2005, in Honolulu, Hawaii. All of these meetings are open to all interested parties. The annual meetings of both the American Society for Surgery of the Hand and the American Association for Hand Surgery accept free papers, but both also offer instructional courses and symposia, many of which include hands-on sessions. Over the years, as with other maturing organizations, the trend has been for fewer free papers and more symposia and hands-on workshops, including many non-CME-credit industry-sponsored workshops in facilities adjacent to the accredited scientific meeting. Membership in the two hand surgery societies is restricted to those who have had specific hand surgery training and, in the case of the American Society for Surgery of the Hand, those who have received the Certificate of Added Qualifications in Hand Surgery offered by the American Boards of Orthopaedic Surgery, Plastic Surgery, and Surgery. Further information on membership as well as on any of the above meetings can be obtained by contacting the organizations directly. Finally, both organizations maintain active web sites, with educational and informational content directed to the public and interested medical professionals as well as members. American Society for Surgery of the Hand (ASSH): 6300 North River Road, Suite 600, Rosemont, IL 60018-4256. Telephone: 847-384-8300. Web site: www.hand-surg.org. American Association for Hand Surgery (AAHS): 20 North Michigan Avenue, Suite 700, Chicago, IL 60602. Telephone: 312-236-3307. Web site: www.handsurgery.org.
The editorial staff of The Journal reviewed a large number of recently published research studies related to the musculoskeletal system that received a Level of Evidence grade of I. Over 100 medical journals were reviewed to identify these articles, which all have high-quality study design. In addition to articles published previously in this journal or cited already in this Update, seven level-I articles were identified that were relevant to hand surgery. A list of those titles is appended to this review after the standard bibliography. We have provided a brief commentary about each of the articles to help to guide your further reading, in an evidence-based fashion, in this subspecialty area.
O'Connor D, Marshall S, Massy-Westropp N. Non-surgical treatment (other than steroid injection) for carpal tunnel syndrome. Cochrane Database Syst Rev. 2003(1):CD003219 . Current evidence indicates that oral steroids, splinting, ultrasound, yoga, and carpal bone mobilization may provide substantial short-term benefit for patients with carpal tunnel syndrome. These treatments may have a role in the nonoperative management of carpal tunnel syndrome. In contrast, vitamin B6, diuretics, and oral nonsteroidal anti-inflammatory medication showed no benefit. Maneerit J, Sriworakun C, Budhraja N, Nagavajara P. Trigger thumb: results of a prospective randomised study of percutaneous release with steroid injection versus steroid injection alone. J Hand Surg [Br].2003 ;28:586 -9.[Medline] In this study, 127 thumbs in 115 adults were randomized to percutaneous release with steroid injection or to steroid injection alone. The percutaneous release was done in the office with an 18-gauge needle. The combined treatment was associated with a 91% rate of satisfactory results, whereas the single injection was associated with a 47% rate of satisfactory results. While the combined procedure appeared to provide better results, it is associated with a risk of iatrogenic injury to the digital nerves, which is not a problem that is associated with injection alone. Furthermore, as noted earlier in this update, if multiple injections are permitted, a similar success rate (90%) can be achieved. Horton TC, Hatton M, Davis TR. A prospective randomized controlled study of fixation of long oblique and spiral shaft fractures of the proximal phalanx: closed reduction and percutaneous Kirschner wiring versus open reduction and lag screw fixation. J Hand Surg [Br].2003 ;28:5 -9.[Medline] Thirty-two patients were entered into the study. Fifteen patients who had been managed with Kirschner wires and thirteen who had been managed with lag screws were reviewed at a mean of forty months. There was no significant difference between the groups with regard to the recovery rate, pain, malunion, strength, or motion. Although the abstract states that the recovery rate was the same for both groups, the text only states that patients were evaluated a minimum of fifteen months after the injury. Thus, it is not clear from the data presented that the speed of return to full activity was similar in the two groups. Eight patients in the screw-fixation group had a malunion. I do not understand why this complication occurred. Given that these fractures were all long, oblique fractures and thus were ideal for stable, anatomic lag-screw fixation, it is not clear why the malunion rate was so high in the lag-screw group. However, I do agree with the authors that both techniques are suitable for the treatment of this type of injury. Golash A, Kay A, Warner JG, Peck F, Watson JS, Lees VC. Efficacy of AD-CON-T/N after primary flexor tendon repair in Zone II: a controlled clinical trial. J Hand Surg [Br]. 2003;28:113 -5.[Medline] This was a prospective, randomized trial in which eighty-two tendons in fifty digits of forty-five patients were treated with a 4-0 Prolene Kessler repair and early active motion. ADCON-T/N was injected into the tendon sheath after tenorrhaphy in the study group, whereas no ADCON-T/N was used in the control group. There was no significant difference between the treatment groups, although the ADCON group did have an insignificantly greater rate of rupture at the repair site (30% compared with 20%). ADCON is a resorbable mixture of porcine gelatin and a polyglycan ester that acts as a physical barrier and inhibits adhesion formation. The study was terminated early because of the higher risk of rupture in the ADCON group. This material does not appear to provide any advantages in association with tendon repair. It has been reported to be effective following tenolysis, but not in any peer-reviewed, randomized, controlled trials. The high rupture rate may be related to the aggressive rehabilitation program and the two-strand Prolene repair. Many hand surgeons favor a four-strand repair with 3-0 braided suture when early active motion is used. Kele H, Verheggen R,
Bittermann HJ, Reimers CD. The potential value of ultrasonography in the
evaluation of carpal tunnel syndrome. Neurology.2003
;61:389
-91. A total of 110 wrists in seventy-seven patients with a clinical diagnosis of carpal tunnel syndrome were evaluated with ultrasonography and electrodiagnostic tests, and fifty-five hands in thirty-three asymptomatic volunteers were evaluated with ultrasonography. The ultrasonographer was blinded to the clinical diagnosis. The sensitivity of an increased median nerve cross section (>0.11 cm2) and evidence of compression on longitudinal scans was similar to that of electrodiagnosis (89% compared with 90%). The specificity of the ultrasonographic measures was >98%. The specificity of electrodiagnosis could not be determined because normal subjects were not studied. While not a physiological measure, ultrasonography is noninvasive and is not painful. It appears to offer promise as a diagnostic test in the evaluation of carpal tunnel syndrome. Wong KC, Hung LK, Ho PC, Wong JM. Carpal tunnel release. A prospective, randomised study of endoscopic versus limited-open methods. J Bone Joint Surg Br.2003 ;85:863 -8. Thirty patients with bilateral carpal tunnel syndrome were studied. Each patient was managed with simultaneous bilateral release, with one side treated with a two-portal endoscopic method and the other side treated with a limited open method with the "Indianatome" as described by Strickland. Each hand was randomly allocated to one of the two treatment methods. The patients were reviewed at two, four, eight, sixteen, twenty-six, and fifty-two weeks after surgery. The only significant clinical difference was that there was less palmar tenderness, at all time-points, on the side that had been treated with the "Indianatome." Subjective evaluation revealed that the patients preferred the "Indianatome" side as well. Stevenson J, McNaughton G, Riley J. The use of prophylactic flucloxacillin in treatment of open fractures of the distal phalanx within an accident and emergency department: a double-blind randomized placebo controlled trial. J Hand Surg [Br]. 2003;28:388 -94.[CrossRef][Medline] A total of 193 patients with open fractures of the fingertip were studied. All patients had surgical débridement and primary wound closure. All patients were given a packet of identical-appearing capsules to take postoperatively; the capsules contained either flucloxacillin or lactose. The overall infection rate was 4%, with no difference between the antibiotic and placebo groups.
In support of his research or preparation of this manuscript, the author received grants or outside funding from the National Institutes of Health. The author did not receive payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, educational institution, or other charitable or nonprofit organization with which the author is affiliated or associated.
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