Surgical restoration of the upper limb in cervical spinal cord injury patients

Prior to the 1950s, relatively few patients who suffered a transection of the cervical spinal cord survived their injury. Improved medical care and better coordination have resulted in greater numbers of patients surviving and leaving the hospital. The pioneering work of individual surgeons during the 1960s and 1970s stimulated interest in surgical restoration of upper limb function in tetraplegic patients. Since the publication of Moberg's monograph in 1978, surgical improvement of the upper limbs is regarded as one of the options that should be offered to tetraplegic individuals to improve their function. Patients are classified according to the level of spinal cord injury and the residual motor function (international classification: groups 1 to 9). Surgical procedures are adapted to the motor level for each group of patients. Indications for these procedures are well standardized, the techniques are well mastered, and predictable results can be expected. New nerve transfer techniques have been developed in recent years; they are currently being evaluated.

Access to surgical upper extremity care for people with tetraplegia: an international perspective

STUDY DESIGN

Survey.

OBJECTIVES

To determine whether upper extremity reconstruction in patients with tetraplegia is underutilized internationally and, if so, what are the barriers to care.

SETTING

International-attendees of a meeting in Paris, France.

METHODS

One hundred and seventy attendees at the Tetrahand meeting in Paris in 2010 were sent a 13-question survey to determine the access and utilization of upper limb reconstruction in tetraplegic patients in their practice.

RESULTS

Respondents ranged the globe including North America, South America, Europe, Asia and Australia. Fifty-nine percent of respondents had been practicing for more than 10 years. Sixty-four percent of respondents felt that at least 25% of people with tetraplegia would be candidates for surgery. Yet the majority of respondents found that <15% of potential patients underwent upper extremity reconstruction. Throughout the world direct patient referral was the main avenue of surgeons meeting patients with peer networking a distant second. Designated as the top three barriers to this care were lack of knowledge of surgical options by patients, lack of desire for surgery and poor referral patterns to appropriate upper extremity surgeons.

CONCLUSION

The results of this survey, of a worldwide audience, indicate that many of the same barriers to care exist regardless of the patient's address. This was a preliminary opinion survey and thus the results are subjective. However, these results provide a roadmap to improving access to care by improving patient education and interdisciplinary physician communication.

Biomechanics of the Steindler flexorplasty surgery: a computer simulation study

PURPOSE

Our goal was to investigate the capacity of a Steindler flexorplasty to restore elbow flexion to persons with C5-C6 brachial plexus palsy. In this procedure the origin of the flexor-pronator mass is moved proximally onto the humeral shaft. We examined how the choice of the proximal attachment site for the flexor-pronator mass affects elbow flexion restoration, especially considering possible side effects including limited wrist and forearm motion owing to passive restraint from stretched muscles.

METHODS

A computer model of the upper extremity was used to simulate the biomechanical consequences of various surgical alterations. Unimpaired, preoperative, and postoperative conditions were simulated. Seven possible transfer locations were used to investigate the effects of choice of transfer location.

RESULTS

Each transfer site produced a large increase in elbow flexion strength. Transfer to more proximal attachment sites also produced large increases in passive resistance to wrist extension and forearm supination.

CONCLUSIONS

To reduce detrimental side effects while achieving clinical goals our theoretical analysis suggests a transfer to the distal limit of the traditional transfer region.

Gene expression of transforming growth factor beta isoforms in interposition nerve grafting

Scar production and neuroma formation at nerve graft coaptation sites may limit axonal regeneration and impair functional outcome. Transforming growth factor beta (TGF-beta) is a family of growth factors that is involved in scar formation, wound healing, and nerve regeneration. Fifteen adult Sprague-Dawley rats underwent autogenous nerve grafting. The nerve grafts were analyzed by in situ hybridization to determine the temporal and spatial expression of TGF-beta1 and TGF-beta3 messenger RNA (mRNA). The grafted nerves showed increased expression of TGF-beta1 and TGF-beta3 mRNA in the nerve and the surrounding connective tissue during the first postoperative week. These data suggest that modulation of TGF-beta levels in the first postoperative week may be effective in helping to control scar formation and improve nerve regeneration.

Efficacy of an implanted neuroprosthesis for restoring hand grasp in tetraplegia: a multicenter study

OBJECTIVE

To evaluate an implanted neuroprosthesis that allows tetraplegic users to control grasp and release in 1 hand.

DESIGN

Multicenter cohort trial with at least 3 years of follow-up. Function for each participant was compared before and after implantation, and with and without the neuroprosthesis activated.

SETTING

Tertiary spinal cord injury (SCI) care centers, 8 in the United States, 1 in the United Kingdom, and 1 in Australia.

PARTICIPANTS

Fifty-one tetraplegic adults with C5 or C6 SCIs.

INTERVENTION

An implanted neuroprosthetic system, in which electric stimulation of the grasping muscles of 1 arm are controlled by using contralateral shoulder movements, and concurrent tendon transfer surgery. Assessed participants' ability to grasp, move, and release standardized objects; degree of assistance required to perform activities of daily living (ADLs), device usage; and user satisfaction.

MAIN OUTCOME MEASURES

Pinch force; grasp and release tests; ADL abilities test and ADL assessment test; and user satisfaction survey.

RESULTS

Pinch force was significantly greater with the neuroprosthesis in all available 50 participants, and grasp-release abilities were improved in 49. All tested participants (49/49) were more independent in performing ADLs with the neuroprosthesis than they were without it. Home use of the device for regular function and exercise was reported by over 90% of the participants, and satisfaction with the neuroprosthesis was high.

CONCLUSIONS

The grasping ability provided by the neuroprosthesis is substantial and lasting. The neuroprosthesis is safe, well accepted by users, and offers improved independence for a population without comparable alternatives.

Surgeon-patient barrier efficiency monitored with an electronic device in three surgical settings

Blood-borne viral pathogens are an occupational threat to health care workers (HCWs), particularly those in the operating room. A major risk is posed by accidental penetrating injury, but skin contamination with body fluids from an infected patient, with prolonged intimate cutaneous contact, is a frequent occurrence during surgery, carrying further risk of transdermal infection. We have monitored barrier failure in three surgical settings (microsurgery, orthopedic surgery, general surgery) by means of an electronic surveillance device. A total of 111 surgical procedures were monitored: 67 microsurgeries, 22 orthopedic surgeries, and 22 general surgeries. Of the 278 electronic alarms signaling barrier failure, 44 (15.8%) were associated with glove perforation, 39 of which (88.6%) were not perceived by the operator. In 16 of those, the skin was visibly stained with the patient's blood. Altogether, 76 of the alarms (27.3%) were consequent to contacts caused by soaked gowns/sleeves, and 121 (43.5%) were attributed to hydration of latex porosities; 37 alarms (13.4%) were unexplained false positives. On only one occasion did a surgeon observe blood stains on his hands without a previous alarm; this event was classified as a device failure due to incorrect wiring. Double-gloving offered satisfactory protection against skin contamination during microsurgery but not during orthopedic surgery. The data presented here indicate that electronic monitoring of the surgical barrier enables prompt detection of barrier failure, especially at the level of the gloves, thereby limiting skin contamination with patients' body fluids during surgery.

Activation patterns of the thumb muscles during stable and unstable pinch tasks

The ability to direct forces between the thumb and fingers is important to secure objects in the hand. We compared the coordination of thumb musculature in key and opposition pinch postures between stable and unstable tasks. The unstable task (producing thumb-tip force wearing a beaded thimble) required well-directed forces; the stable task (producing thumb-tip force against a pinch meter) did not. Fine-wire electromyography of thumb muscles and thumb-tip force magnitudes were recorded. We found no statistical differences in thumb-tip force between postures or stable versus unstable tasks, indicating that the highest magnitudes of force can be accurately directed. Abductor pollicis brevis and extensor pollicis longus were significantly more activated in the unstable tasks, suggesting their importance in directing thumb-tip force. Understanding how pinch forces are directed might influence the choice of muscle-tendon transfers performed to restore function to the severely paralyzed thumb. We introduce a device to quantify the ability to control pinch force magnitude and direction simultaneously.

Improvement of Schwann cell attachment and proliferation on modified hyaluronic acid strands by polylysine

Hyaluronic acid (HyA) has the intrinsic ability to promote cell proliferation and reduce scar formation. However, the clinical use of HyA has so far been limited because of its water solubility and nonadhesive characteristics. Increasing interest in HyA as a clinically useful biomaterial has prompted our study of altering HyA's physical properties to render it a potential component of nerve grafts. In this study, strands of HyA were cross-linked by glutaraldehyde (Glut), coated with polylysine, and then inoculated with Schwann cells (SCs). Results in vivo and in vitro demonstrated that cross-linked HyA strands were water insoluble and thus less biodegradable. Poly-D-lysine-resurfaced strands showed significant SC attachment of 350-400 cells/mm(2), compared to uncoated controls (0-10 cells/mm(2), p < 0.01). Fibroblast control groups showed an attachment of 40-100 cells/mm(2) on coated strands. Immunostaining for proliferating cells showed SCs as and fibroblasts as +. Cells neither adhered to nor proliferated on the modified HyA strands that were not resurfaced. The results suggest that polylysine promotes SC attachment and proliferation to glutaraldehyde-cross-linked HyA strands, the product being a three-dimensional composite with low solubility that may have potential application in nerve grafts.

Quantification of fingertip force reduction in the forefinger following simulated paralysis of extensor and intrinsic muscles

Objective estimates of fingertip force reduction following peripheral nerve injuries would assist clinicians in setting realistic expectations for rehabilitating strength of grasp. We quantified the reduction in fingertip force that can be biomechanically attributed to paralysis of the groups of muscles associated with low radial and ulnar palsies. We mounted 11 fresh cadaveric hands (5 right, 6 left) on a frame, placed their forefingers in a functional posture (neutral abduction, 45 degrees of flexion at the metacarpophalangeal and proximal interphalangeal joints, and 10 degrees at the distal interphalangeal joint) and pinned the distal phalanx to a six-axis dynamometer. We pulled on individual tendons with tensions up to 25% of maximal isometric force of their associated muscle and measured fingertip force and torque output. Based on these measurements, we predicted the optimal combination of tendon tensions that maximized palmar force (analogous to tip pinch force, directed perpendicularly from the midpoint of the distal phalanx, in the plane of finger flexion-extension) for three cases: non-paretic (all muscles of forefinger available), low radial palsy (extrinsic extensor muscles unavailable) and low ulnar palsy (intrinsic muscles unavailable). We then applied these combinations of tension to the cadaveric tendons and measured fingertip output. Measured palmar forces were within 2% and 5 degrees of the predicted magnitude and direction, respectively, suggesting tendon tensions superimpose linearly in spite of the complexity of the extensor mechanism. Maximal palmar forces for ulnar and radial palsies were 43 and 85% of non-paretic magnitude, respectively (p<0.05). Thus, the reduction in tip pinch strength seen clinically in low radial palsy may be partly due to loss of the biomechanical contribution of forefinger extrinsic extensor muscles to palmar force. Fingertip forces in low ulnar palsy were 9 degrees further from the desired palmar direction than the non-paretic or low radial palsy cases (p<0.05).

Hand and wrist injuries in young athletes

Successful treatments of musculoskeletal injuries in the pediatric population demand a thorough understanding of the basic anatomy and its biomechanics, and the physiology of growth and development of the immature skeleton. In addition, good treatment outcomes rely on the treating physician being an effective teacher to the young athlete and the patient's parents, coaches, and trainers. At the same time, the physician must be a good student in learning the nature of the patient's sports and each patient's athletic ability and aspirations. Most pediatric hand and wrist injuries can be treated nonoperatively with proper immobilization techniques and activity modification, but cases requiring surgical intervention must be recognized promptly to avoid long-term complications.

A virtual-reality-based telerehabilitation system with force feedback

A PC-based orthopedic rehabilitation system was developed for use at home, while allowing remote monitoring from the clinic. The home rehabilitation station has a Pentium II PC with graphics accelerator, a Polhemus tracker, and a multipurpose haptic control interface. This novel interface is used to sample a patient's hand positions and to provide resistive forces using the Rutgers Master II (RMII) glove. A library of virtual rehabilitation routines was developed using WorldToolKit software. At the present time, it consists of three physical therapy exercises (DigiKey, ball, and power putty) and two functional rehabilitation exercises (peg board and ball game). These virtual reality exercises allow automatic and transparent patient data collection into an Oracle database. A remote Pentium II PC is connected with the home-based PC over the Internet and an additional video conferencing connection. The remote computer is running an Oracle server to maintain the patient database, monitor progress, and change the exercise level of difficulty. This allows for patient progress monitoring and repeat evaluations over time. The telerehabilitation system is in clinical trails at Stanford Medical School (CA), with progress being monitored from Rutgers University (NJ). Other haptic interfaces currently under development include devices for elbow and knee rehabilitation connected to the same system.

Polypeptide resurfacing method improves fibroblast's adhesion to hyaluronan strands

Hyaluronic acid (hyaluronan, HyA) is a matrix component that takes part in cell adhesion and growth in normal and repaired tissues. Since it is soluble in water, HyA has been of limited use in tissue engineering of artificial matrices. Recent studies demonstrate that polypeptides have the twin advantages of reducing solubility of HyA and improving cellular attachment via cell surface adhesion molecule receptors. This paper describes a new approach of using a polypeptide resurfacing method to enhance the attachment of cells to HyA strands. HyA strands were crosslinked by glutaraldehyde and then resurfaced with poly-D-lysine, poly-L-lysine, glycine, or glutamine. After inoculation with fibroblasts in vitro, modified HyA was evaluated with histological and immunohistochemical staining methods for cell adhesion and proliferation. Modified HyA with fibroblast cells also were implanted in vivo. The results show that (1) both polylysines enhanced fibroblast adhesion to crosslinked HyA strands; (2) HyA strands were able to be crosslinked well by 3 days of treatment in glutaraldehyde, and as a biomaterial they could resist biodegradation; (3) modified HyA has good biocompatibility, both in vitro and in vivo. The results demonstrate that HyA material resurfaced by polypeptides has positive advantages for cellular adhesion. Resurfaced HyA has much potential as an improved biomaterial for clinical usage.

Fine-wire electromyographic recording during force generation. Application to index finger kinesiologic studies

When accurately placed, fine-wire electrodes (FWEs) permit selective electromyographic recording during kinesiologic studies; however, their potential to limit contraction of the index finger muscles has not previously been evaluated. Given that these electrodes cannot be reinserted, reliable techniques are necessary to achieve proper placement while minimizing subject discomfort and electrode waste. The small size, close arrangement, and anatomic variability of hand and forearm muscles create challenges to achieving these goals. In this study, we simultaneously measured maximal fingertip forces and fine-wire electromyographic signals from all seven muscles of the index finger. Forces in five directions, with and without FWEs in place, were not statistically different (repeated-measures analysis of variance, P < 0.46) in five healthy adult subjects. To guide electrode placement, we identified skin penetration landmarks, direction of needle advancement, and depth of muscle fibers. Fibers of flexor digitorum superficialis and flexor digitorum profundus to the index finger were more distal than depicted in textbooks, requiring electrode placement at or distal to the midpoint of the forearm. For these muscles and the extensor digitorum, locating the desired fibers first with a monopolar needle electrode facilitated subsequent FWE placement. For the dorsal and palmar interossei, lumbrical, and extensor indicis proprius, insertion was aided by concurrent monitoring of the electromyographic signals. We achieved a 93% success rate during FWE placement in a total of 60 muscles. Techniques for recording from each of the seven index finger muscles are described.

Enhancement of axon growth by detergent-extracted nerve grafts

BACKGROUND

The immunogenicity of nerve allografts is responsible for their rejection. We have developed a method for preparing cell-free nerve grafts using lysophosphatidylcholine to remove cells, axons, and myelin sheaths.

METHODS

The remaining intact nerve extracellular matrix is the extracted nerve graft (eNG). Cultured neonatal Schwann cells were micro-injected into the eNG to form recellularized nerve grafts (rNG). eNG, rNG, and normal isografts (15 mm long) were implanted in the peroneal nerves of F-344 rats. Ten rats were given an eNG on the right, and an isograft on the left. Ten rats were given an rNG on the right, and a sham operation on the left. Sham operation was used as the control and the isograft was used as the benchmark procedure. Walking track analysis was performed every 15 days after surgery to determine the peroneal functional index. Morphometric analysis of the distal peroneal nerve and extensor digitorum muscle weight were analyzed 3 months after surgery.

RESULTS

The three types of grafted legs had the classical effect observed after peripheral nerve repair, with decreased functional ability, decreased target muscle weight, fewer large nerve fibers, and more small nerve fibers. Isografts, eNG, and rNG all had similar patterns of peroneal functional index improvement after implantation. The extensor digitorum longus muscle weight and axon counts for the three types of graft were not statistically different. Hence, eNG and rNG can enhance nerve regeneration in the same way as isografts. The host Schwann cells that invaded the implanted eNG probably acted in the same fashion as the cultured Schwann cells injected into the rNG and the resident cells of isografts.

CONCLUSIONS

The great permeability of the longitudinally oriented matrix of eNG to cells is, therefore, a major advantage over the reported poor permeability of freeze-thawed nerve grafts.

Vascularized toe joint transfer to the hand

From 1984 to 1993, 36 vascularized toe joints were transferred in 33 patients. The present study group excludes 3 toe joint transfers to elbow and temporomandibular joints and 4 toe joint to hand transfers lost to follow-up. The final study group includes 29 vascularized toe joint transfers in 27 patients, 21 males and 6 females. All were performed for posttraumatic reconstruction, except one transfer for congenital deformity. Follow-up averaged 32.4 months. Mean range of motion was 34 degrees in toe metatarsophalangeal joint to hand metacarpophalangeal joint transfers, 32 degrees in toe proximal interphalangeal joint to hand metacarpophalangeal joint transfers, and 24 degrees in toe proximal interphalangeal joint to hand proximal interphalangeal joint transfers. Although vascularized toe joint transfer is an alternative to arthrodesis, in order to have a greater range of motion than average, the patient must have well-functioning muscle and associated tendons effecting joint motion. Good results were obtained in two immediate free vascularized toe joint transfers to complex injuries involving loss of the metacarpophalangeal joint. We encourage toe joint transfer in selected complex hand injuries.

Action potentials of curved nerves in finite limbs

Previous simulations of volume-conducted nerve-fiber action-potentials have modeled the limb as semi-infinite or circularly cylindrical, and the fibers as straight lines parallel to the limb surface. The geometry of actual nerves and limbs, however, can be considerably more complicated. This paper presents a general method for computing the potentials of fibers with arbitrary paths in arbitrary finite limbs. It involves computing the propagating point-source response (PPSR), which is the potential arising from a single point source (dipole or tripole) travelling along the fiber. The PPSR can be applied to fibers of different conduction velocities by simple dilation or compression. The method is illustrated for oblique and spiralling nerve fibers. Potentials from oblique fibers are shown to be different for orthodromic and antidromic propagation. Such results show that the straight-line models are not always adequate for nerves with anatomical amounts of curvature.

Short gracilis myocutaneous flaps for vulvoperineal and inguinal reconstruction

From October of 1990 to April of 1993, 16 short gracilis myocutaneous flaps and 1 short gracilis muscular flap were used to reconstruct vulvoperineal, inguinal, perineal, and ischial soft-tissue defects. Five of the 6 bilateral myocutaneous flaps were used for vulvoperineal reconstruction after radical vulvectomy combined with partial vaginectomy and one radical vulvectomy. Four unilateral myocutaneous flaps and one muscular flap were used for inguinal, suprapubic, ischial, and perineal reconstruction after release of contracted scar or excision of an ischial pressure sore. The immediate complications consisted of partial necrosis of the distal third of the cutaneous tissue in 6 patients, 1 superficial cutaneous necrosis, and superficial wound infection in 7 patients. The muscular portion of the flaps all survived. The follow-up period was from 6 to 27 months. The short gracilis flap has greater mobility than the classically described gracilis flap. On the basis of the functional and cosmetic results, the short gracilis flap is an excellent alternative to the more bulky classic gracilis flap.

Extensor digiti minimi tendon transfer to prevent recurrent ulnar drift

Thirty percent of patients with rheumatoid arthritis develop ulnar drift. Although numerous operations have been described, recurrence of the deformity is frequent. We recommend use of the extensor digiti minimi tendon transfer to prevent recurrent ulnar deviation. The tendon insertion is moved from a dorsal location to a dorsal-radial position. In this new location, the tendon produces both extension and radial deviation. Moreover, this transfer is maximally effective in extension when ulnar drift is greatest. We have used this transfer 28 times during the past 6 years. In evaluating patients more than 1 year after surgery, metacarpal phalangeal joint extension averaged 52 degrees and there was no evidence of recurrent ulnar drift of the little finger. The only problem was slight hyperextension of less than 5 degrees in approximately half of the patients. However, in no patient was this functionally a problem. We recommend the use of this tendon transfer in all patients with ulnar drift undergoing metacarpal phalangeal joint replacement for rheumatoid arthritis.

The nerve gap dilemma: a comparison of nerves repaired end to end under tension with nerve grafts in a primate model

The objective of this study was to compare, in a clinically relevant primate model, axon regeneration after epineurial repair under tension (15 mm gap) with interfascicular nerve grafts with the use of either standard microsuture techniques or a new interfascicular nerve graft technique termed fascicular tubulization that uses a hypoantigenic collagen membrane formed into a tube to approximate nerve ends. Electrophysiologic analysis demonstrated that the percentage of proximal axons that conducted across the repair site was greater in those nerves repaired under tension with epineurially placed sutures than in either of the tensionless repairs involving interfascicular graft techniques. The mean diameters of the regenerated axons repaired under tension with epineurial sutures were greater than those of the nerves repaired with interfascicular grafts, although the difference was not statistically significant. Interfascicular nerve grafting with tubulization using the current collagen tube resulted in regeneration equal to the sutured interfascicular nerve grafts. For modest defects (perhaps up to 3 to 4 cm in the adult), it seems advantageous to accept the modest tension associated with an epineurial repair rather than to use an autograft (or artificial graft) to achieve a tension-free repair.

Efficacy of immobilization following aspiration of carpal and digital ganglions

In a prospective study 69 carpal and digital ganglions were aspirated, multiply punctured, and digitally ruptured. Fifty percent of the wrists and digits were immobilized for 3 weeks and 50% were mobilized early. Follow-up was 1 year. Immobilization in our study did not significantly improve the results of treatment. During the course of the study, 51% of all ganglions did not recur. The outcome was successful in 52% of the wrists and digits that were immobilized and in 50% of those that were not. Forty-six percent of the dorsal carpal ganglions did not recur. Treatment was successful in 48% of dorsal carpal ganglions in which the wrists were immobilized and in 45% of those that were not. Similar percentages were found for palmar and digital ganglions. From our results, we conclude that immobilization does not significantly improve the successful treatment of ganglions over perforation and aspiration alone.

The pulp plasty: a composite graft for complete syndactyly fingertip separations

Composite grafts of skin and subcutaneous fat harvested from the glabrous non-weight-bearing areas of the foot were used to graft 34 fingertips after separation of 23 complete syndactyly webs in 13 patients. Simple complete syndactylies accounted for 17% and complex complete syndactylies accounted for 83%; synonychia was encountered in 70%. Follow-up averaged 13.9 months (minimum, 2 months, maximum 33 months). All patients had 100% take of the composite graft. Subjective gradings were 94% good, 6% fair, and there were no poor results. This technique provides a relatively normal contour and satisfactory pad to the fingertip.

A comparison of suture and tubulization nerve repair techniques in a primate

This study compared standard methods of nerve repair, epineurial or perineurial sutures with a technique termed fascicular tubulization using a biodegradable polyglycolic acid tube in a nonhuman primate model. Electrophysiologic analysis demonstrated that the percentage of proximal axons that conducted across the repair site did not significantly differ among the three techniques while epineurial suture repairs were associated with significantly longer conduction delays across the repair site compared with the other two techniques. Even though fascicular tubulization using the current polyglycolic acid tube resulted in regeneration equal to the currently perceived best suture repair technique, associated technical problems with the current tube design indicate that this fascicular tubulization technique cannot, at present, be considered as an alternative to present clinically used nerve suture techniques.

Brachial plexus microsurgery in children

From this review, the following points have emerged: 1. The typical obstetrical palsy is a traumatic lesion caused by forced lowering of the shoulder during delivery. 2. While the lesion may affect all the roots, the upper roots are usually ruptured, whereas the lower roots (if involved) are always avulsed. 3. Spontaneous recovery is possible, but its quality depends on how early recovery of previously paralyzed muscles begins. If the biceps have not started to recover by 3 months, the final result will be poor. It is at this time interval that a surgical decision should be made. 4. Surgical repair is always possible, usually by grafting, though repair can be difficult if significant numbers of avulsions have occurred. 5. The results of surgical reconstruction are better than are the results of spontaneous evolution, at least in those patients who reach the age of 3 months without evidence of recovery of the biceps. For example, more than half of the patients recover a nearly normal shoulder after grafting C5, C6 lesions in Gilbert's series, whereas in the same control population of patients, none achieved this result spontaneously. 6. Palliative treatment of the sequelae of birth palsies is difficult, and the results obtained are rarely totally satisfactory. It is for these reasons that the initial surgical intervention should be on the plexus itself in those instances meeting the criteria established above. It is important to make this decision as quickly as possible before neuroplasticity is diminished and joint contractions have occurred.

Digit replantation applying the leech Hirudo medicinalis

Digits that were formerly assessed as nonreplantable may now be replanted with the help of the leech Hirudo medicinalis. The early experience with a series of patients who had relative contraindications for replantation is reported. In each case, venous repair was either marginal or technically impossible. Postoperative venous congestion developed following replantation and was treated with the application of medicinal leeches. Patient acceptance was high, and no infections developed. No patient required transfusion. The authors conclude that the use of medicinal leeches shows promise as a safe and effective method of providing temporary venous drainage in replanted digits.

Fascicular tubulization: a comparison of experimental nerve repair techniques in the cat

Peripheral nerve repair remains one of the most difficult problems in hand surgery; the results of conventional epineurial and fascicular suture repair are a major limitation to the rehabilitation of the patient. The aim of this study was to evaluate a tubulization technique of nerve repair by wrapping a membrane of hypoantigenic collagen around the nerve at the fascicular level. Cat ulnar and median nerves were used as a multifascicular nerve model. Thirty-eight animals were studied. Ten animals were included in long-term studies comparing fascicular tubulization to either epineurial suture or fascicular suture nerve repair. Histologically, the tube repairs demonstrated improved organization at the repair site compared with either suture technique. Tube repair is not significantly different statistically by quantitative histological and physiological evaluation methods from epineurial suture or fascicular suture repairs. Further studies in more clinically applicable animal models are required before this technique can be considered as an alternative to present clinical nerve suture techniques.

Experience with the island radial forearm flap in local hand coverage

Use of the island radial forearm flap (RFF) for soft-tissue coverage of hand and forearm following mutilating injuries, chemotherapeutic injection sloughs, and tumor excisions are discussed. Twenty-eight flaps were used in 28 injured upper extremities. Partial flap loss occurred in three patients. Minor sloughing of the skin graft of the donor site occurred in four. Twelve patients had persistent dysesthesias and paresthesias in the injured extremity. All patients complained of some degree of weakness in the injured extremity. Our experience supports the use of this flap for local hand and forearm coverage when local tissue is unavailable and skin grafting is deemed inadvisable. Donor site problems have been acceptable in our patient population.

Effect of low frequency low energy pulsing electromagnetic field (PEMF) on X-ray-irradiated mice

C3H/Km flora-defined mice were used to investigate the effect of exposure to pulsing electromagnetic field (PEMF) after total body x-ray irradiation. Prolonged exposure to PEMF had no effect on normal nonirradiated mice. When mice irradiated with different doses of x-ray (8.5 Gy, 6.8 Gy, and 6.3 Gy) were exposed to PEMF 24 h a day, we observed a more rapid decline in white blood cells (WBC) in the peripheral blood of mice exposed to PEMF at all the x-ray dosages used. No effect of exposure to PEMF was observed on the survival of the mice irradiated with 6.3 Gy and 8.5 Gy; in mice irradiated with 6.8 Gy, 2 out of 12 survived when exposed to PEMF as compared to 10 out of 12 control mice that were irradiated only. At day 4 after irradiation autoradiographic studies performed on bone marrow and spleen of 8.5-Gy-irradiated mice showed no difference between controls and mice exposed to PEMF, whereas on 6.8-Gy mice the bone marrow labeling index was lower in mice exposed to PEMF. In mice irradiated to 6.3 Gy we observed that the recovery of WBC in the peripheral blood was slowed in mice exposed to PEMF and their body weight was significantly lower than in control mice that were irradiated only. The spleen and bone marrow of the mice irradiated to 6.3 Gy and sacrificed at days 4, 14, 20, and 25 after irradiation were analyzed by autoradiography to evaluate the labeling index. Half of the spleens from mice sacrificed at day 25 after irradiation were used to evaluate the RNA content. Autoradiography showed that in the spleen and bone marrow of control mice, there were more cells labeled with [3H]thymidine at days 4 and 14 and less at days 20 and 25 after irradiation in comparison with mice irradiated and exposed to PEMF. The Northern blot analysis of histone H3 and p53 protein RNAs extracted from the spleens at day 25 after irradiation showed a slight increase in cycling cells among spleens of mice exposed to PEMF. We suggest that the exposure to PEMF immediately after x-ray irradiation results in increased damage.

Neurotization in brachial plexus injuries. Indication and results

In neurotization or nerve transfer, a healthy but less valuable nerve or its proximal stump is transferred in order to reinnervate a more important sensory or motor territory that has lost its innervation through irreparable damage to its nerve. In brachial plexus injuries, extraplexal nerves such as the spinal accessory nerve, rami of the cervical plexus, or intercostal nerves are transferred onto trunks, cords, or individual nerves or else segments of the brachial plexus that maintain continuity with the spinal cord may be coapted to trunks or cords the surgeon wishes to innervate. This method is particularly indicated in root avulsion injuries that occur frequently following traction trauma to the brachial plexus. The authors convey their experience with neurotization using the long thoracic nerve in seven cases, the accessory nerve in 30 cases, intercostal nerves in 66 cases, and various nerve transfers within the plexus in 31 cases. Results of other authors are also reported. With these methods, it is possible to obtain good elbow flexion in more than one-half of patients; however, only limited shoulder function and no useful finger function are obtained.

An approach to mandibular reconstruction

Mandibular reconstruction requires the restitution of both form and function. Proper preoperative planning, vascularized bone grafts, rigid fixation, flexibility of donor site choices, and restoration of labial, buccal, and lingual sulci lead to optimal reconstruction. We have used this approach in 38 patients; bony survival resulted in 37 and primary union in 35. A main limiting factor exists with individuals who have lost extensive amounts of soft tissue and muscle at the time of tumor resection or trauma. Only by attention to details in the preoperative, intraoperative, and postoperative phases can the best functional and aesthetic results be achieved.

Surgical reconstruction in tetraplegia

The authors reviewed their 10 years of combined experience in the surgical reconstruction of the upper extremities in 170 quadriplegic patients from two spinal cord treatment centers. The authors' current recommendations regarding patient selection are presented, refinements in previously published surgical techniques are defined, and the principles of postoperative care are discussed.

Rubber band as external assist device to provide simple grip for quadriplegic patients

The rubber band as an external assist device provides an effective grip for the hand of high spinal cord injury quadriplegic patients. This technique can also be useful for preoperative patients who are undergoing physical and occupational therapy or to assess patients' needs for surgery. The rubber band as an adaptive device is preferred because of its availability, low visibility, and ease of application. We attempt to provide a more standardized method of the rubber band technique and to popularize it.

Repetitive trauma and nerve compression

Repetitive movement of the upper extremity, whether recreational or occupational, may result in various neuropathies, the prototype of which is the median nerve neuropathic in the carpal canal. The pathophysiology of this process is incompletely understood but likely involves both mechanical and ischemic features. Experimentally increased pressures within the carpal canal produced reproducible progressive neuropathy. Changes in vibratory (threshold-type) sensibility appears to be more sensitive than two-point (innervation density-type) sensibility. The specific occupational etiologies of carpal neuropathy are obscured by methodologic and sociological difficulties, but clearly some occupations have high incidences of CTS. History and physical examination are usually sufficient for the diagnosis, but diagnostic assistance when required is available through electrophysiological testing, CT scanning, and possibly MRI. Each of these tests has limitations in both sensitivity and specificity. Treatment by usual conservative means should be combined with rest from possible provocative activities. Surgical release of the carpal canal is helpful in patients failing conservative therapy. Occupational modifications are important in both treatment and prevention of median neuropathy due to repetitive trauma.

The results of microneurosurgical reconstruction in complete brachial plexus palsy. Assessing outcome and predicting results

The outcome of microsurgical reconstruction in 114 adult patients presenting with complete traumatic brachial plexus palsy was analyzed. The authors examined the effects of age, time since injury, operative findings, and the techniques of reconstruction on the level of muscle recovery. Statistical and analytic computer programs were used in an attempt to determine what factors most influenced recovery.

The radial forearm flap: a versatile source of composite tissue

The radiovolar area of the forearm constitutes a versatile source of composite tissues for pedicle flap reconstruction of the hand and free-flap reconstruction for many areas of the body. The skin is thin and relatively hairless, and the vascular pedicle is long and of large caliber. The flap can be harvested to contain vascularized tendons and bone. The skin can be reliably reinnervated. The principal disadvantage, that this is a conspicuous donor site, has not been a source of concern for our patients. Nineteen of the 20 (95%) free flaps survived completely.

Imaging studies of the cadaver hand using transmission ultrasound

Ultrasonic transmission imaging has already demonstrated potential for evaluating structures in the hand. In this study, a cadaver hand was imaged using a transmission scanner with improved imaging capability. The hand was then frozen and serially sectioned and comparisons were made between the sectional anatomy and the corresponding image. Bone (in silhouette), muscle, cartilage, and tendon were visualized with high resolution.

Application of free tissue transfers to the foot

During the past five years we have used three sources of free tissue transfers in 26 patients to reconstruct defects of the ankle and dorsum, hind, mid- and forefoot, defects poorly or unamenable to traditional reconstructive methods. These included free muscle transfers covered with a skin graft, temporoparietal fascia also covered with a graft, and radial forearm skin or fascia. In addition, six complex defects were reconstructed with composite tissue free transfers, usually tendinocutaneous flaps. There was one partial flap loss. All were successful in both healing the defect and in providing functional restoration, except in the forefoot. From an analysis of these cases, we have developed indications for various transfers based on the functional needs of the area involved and donor site requirements.

Hand reconstruction following avulsion of all dorsal soft tissues. A cutaneo-tendinous free tissue transfer

Restoration of function following mutilating injuries to the extensor surface of the hand has traditionally involved staged reconstruction with distant pedicle flaps, followed by tendon grafting. Advances in microsurgery now permit the transfer, in one operation, of vascularized composite tissues such as skin and muscle, or skin and bone. For dorsal hand reconstruction a composite flap of skin, tendons and nerves from the dorsum of the foot was transferred in one stage soon after injury, avoiding unnecessary disabling scar formation, prolonged hospitalization and resulting in the rapid restoration of near normal function and appearance of the hand. Donor site morbidity was minimal.