Free filet leg flap.

With extensive loss of local soft tissues after resection of a sarcoma, standard closure may not be possible. The large operative defect in this instance may necessitate a free tissue transfer. Use of a vascularized tissue transfer from the leg of the amputated extremity of a patient to close a hemipelvectomy defect is described.

Osteocutaneous radial forearm free flap: its use without significant donor site morbidity.

While the fasciocutaneous radial forearm free flap has gained increasing popularity, the osteocutaneous radial forearm free flap has been condemned because of a high rate of pathologic donor radius fracture. On the basis of studies that demonstrated increased strength in ostectomized radii after dynamic compression plating, we believed that internal fixation at the time of graft harvest would significantly reduce the incidence of donor radius fracture. This is a retrospective review of the first 54 patients undergoing osteocutaneous radial forearm free flap reconstruction of the head and neck at our institution; 52 underwent prophylactic plating of their donor radii. No clinically significant donor radius fractures have occurred in plated patients. Five asymptomatic fractures were discovered on routine radiographs and required no treatment. Objective evaluation of forearm range of motion and strength after graft harvest demonstrated excellent function compared with unoperated arms. Serial radiographs have shown remodeling and reconstitution of donor radii without localized osteopenia.

Preoperative evaluation of the radial forearm free flap patient with the objective Allen's test.

OBJECTIVE: The conventional subjective Allen's test (SAT) can be problematic because of its subjective nature. The objective Allen's test (OAT) was used before surgery to reliably and objectively assess forearm vascular flow in anticipation of harvesting a radial forearm free flap (RFFF) for use in head and neck reconstruction. STUDY DESIGN AND SETTING: Retrospective analysis of 65 patients undergoing both preoperative SAT and OAT was completed at the University of Kansas Medical Center between December 1994 and March 1998. RESULTS: The sensitivity and specificity of the SAT compared with the sensitivity and specificity of the OAT were only 65% and 76%, respectively. In 40 patients with at least 1 forearm with a positive SAT, only 1 (2.5%) patient was found by OAT to have vasculature that would not have allowed safe RFFF harvest in either forearm. In contrast, of the 25 patients with equivocal or negative SAT results in both arms, 18 (72%) were found by OAT to be safe candidates for RFFF harvests. CONCLUSIONS: The OAT is an objective measure of forearm vascular flow and is superior to conventional SAT in RFFF donor-site selection.

Torsional strength of the radius after osteofasciocutaneous free flap harvest with and without primary bone plating.

The osteocutaneous radial forearm free flap (OCRFFF) has not gained widespread popularity in mandibular reconstruction, primarily because of concerns about pathologic fracture of the weakened radius. This study examines the effectiveness of plate fixation of the radius bone after harvest of the OCRFFF as a mechanism to minimize donor-site morbidity and increase the usefulness of the OCRFFF. Matched pairs of fresh human cadaveric radius bones were used in this study. Two study groups were designed. The first group was used to define the amount of strength lost after a typical bone graft harvest. The second group was designed to demonstrate how much torsional strength was regained by the application of an orthopedic reconstruction plate. Statistically significant results were obtained for both groups. In group 1, the strength of the cut bones compared with that of the unaltered bones was significantly decreased by 82% (P = 0.016). In group 2, the cut bones reinforced with a plate were 75% stronger (P = 0.002) than the bones that were only cut. Although the radius bone is significantly weakened by the harvest of a graft, much of this strength can be regained with plate fixation of the radius.

Osteocutaneous radial forearm free flaps. The necessity of internal fixation of the donor-site defect to prevent pathological fracture.

BACKGROUND: Osteocutaneous radial forearm free flaps have fallen from favor due to pathological fractures of the radius. The purposes of this study were to propose a means to decrease the rate of pathological fracture by prophylactic fixation of the donor-site defect and to evaluate this technique biomechanically. METHODS: Two groups of ten matched pairs of fresh-frozen cadaveric radii were harvested. In Group 1, an eight-centimeter length of radius comprising 50 percent of the cross-sectional area of the bone was removed to simulate an osteocutaneous radial forearm donor-site defect. This defect was created in one member of each pair, with the other bone in the pair left intact. In Group 2, both members of the ten matched pairs of radii had identical defects created as previously described. However, one radius in each pair had a twelve-hole, 3.5-millimeter dynamic compression plate placed across the segmental defect. In each group, five matched pairs were tested to failure in torsion and five matched pairs were tested to failure in four-point bending. RESULTS: In Group 1, the intact radius was a mean of 5.7 times stronger in torsion and 4.2 times stronger in four-point bending than the radius with the segmental resection. In Group 2, the radius that was ostectomized and fixed with a plate was a mean of 4.0 times stronger in torsion and 2.7 times stronger in four-point bending than the ostectomized radius. CONCLUSIONS: Removal of an eight-centimeter segment from the radius dramatically decreased both torsion and bending strength. Application of a plate over the defect in the radius significantly restored the strength of the radius (p = 0.01).

Changes in the stress relaxation properties of peripheral nerves after transection.

Changes in peripheral nerve stress relaxation after transection were measured weekly for 5 weeks in the distal stumps of sciatic nerves of 50 Sprague-Dawley rats. Each week after transection the distal stumps of the transected nerves showed decreased stress relaxation compared with the freshly transected contralateral nerves after undergoing a 10% elongation. The transected side always showed less stress relaxation at 30 minutes than the intact contralateral side (average, 24%; range, 15% to 32%). A statistically significant difference in mean stress relaxation between the cut nerves and the uncut sciatic nerves occurred for weeks 1 through 4. Week 5 demonstrated a decrease in mean stress relaxation of the experimental side compared with the contralateral control side but this was not statistically significant. Decreased stress relaxation of the distal stump results in increased tension at the suture line as the nerve gap is overcome when performing a delayed neurorrhaphy at 1 to 5 weeks after transection.

Ulnar nerve strains at the elbow.

Twenty unembalmed intact cadavers had strain measurements taken of the ulnar nerve at 5 positions around the elbow and at varying degrees of elbow flexion. A microstrain gauge was implanted directly into the nerve through a superficial incision. Maximum strains in the ulnar nerve occurred at maximum elbow flexion and directly behind the medial epicondyle; meaningfully less strain was seen at lesser degrees of flexion and positions distal and proximal to the epicondyle. A wide range of maximal strains (0% to 14%) was found. Twenty-five percent of the ulnar nerves showed strains of greater than 10% with maximum elbow flexion behind the medial epicondyle. Cubital tunnel syndrome may be at least in part a traction neuropathy.

Thumb injuries in the athlete.

Sports-related injuries of the thumb, including fractures and dislocations, are very common. The anatomic basis for these injuries is discussed. Treatment options include functional bracing and early operative intervention, thus hastening a return to sporting activities.

A comparison of fixation screws for the scaphoid during application of cyclical bending loads.

UNLABELLED: Matched pairs of scaphoids from cadavera were stressed with ramped intensity cyclical bending loads after osteotomy and fixation of one scaphoid with a Herbert screw and fixation of the other with an AO 3.5-millimeter cannulated screw, a Herbert-Whipple screw, an Acutrak cannulated screw, or a Universal Compression screw. The AO screw, Acutrak screw, and Herbert-Whipple screw demonstrated superior resistance to cyclical bending loads compared with the Herbert screw. The Universal Compression screw did not provide better fixation than the Herbert screw because of fractures that occurred at the time of insertion. The AO screw and the Herbert screw were then tested in a separate setup in which a segment of volar cortex had been removed in addition to the simple osteotomy. The loss of volar cortex greatly diminished the quality of the fixation provided by both of the screws during application of ramped intensity cyclical bending loads. CLINICAL RELEVANCE: A fixation device in the scaphoid must be able to withstand the stresses that are placed on the scaphoid as a result of its position spanning the proximal and distal carpal rows. Also, because of the prolonged time required for healing of fractures or non-unions of the scaphoid, the device must be able to withstand many such cycles of stress. The present study demonstrates that commonly used screws for fixation of the scaphoid vary significantly (p < 0.005) in their ability to resist cyclical bending loads.

Changes in the structural properties of peripheral nerves after transection.

Changes in peripheral nerve structural properties after transection were measured weekly for 5 weeks in the distal stump of the sciatic nerve in 50 Sprague-Dawley rats. Each week after transection, the distal stump of the transected nerve showed increased stiffness when compared to intact nerves. Linear elastic stiffness reached a maximum at weeks 1 and 2 after transection, when the transected nerves were 15% stiffer than the contralateral control sides. Toughness was also increased and reached a maximum at week 4 with a 50% difference between values for experimental and control sides. Overall failure load was between 21% and 27% greater, peaking at week 3. An increase in stiffness of the distal stump would result in increased tension at the suture line, as the nerve gap is overcome when performing a delayed neurorraphy. These data suggest, with respect to structural properties, that an end-to-end repair should be carried out at the time of injury; after only 1 week, significant stiffness in the distal segment of the nerve developed, which should result in an increase in tension at the repair site.

The effect of delayed repair on microvascular patency rates.

The effect of delayed microsurgical arterial anastomosis on the patency rate in the rat femoral artery was evaluated. Sixteen Sprague-Dawley rats underwent ligation and repair of the right femoral arteries and repair of the left artery as a control. The rats were divided into four groups, and their right arteries were ligated for 24, 48, 72, or 96 hr. Patency was evaluated by the standard stripping test and flow after transection of the vessel. At 5 days after the arterial anastomosis, four of 16 arteries remained patent, two of which were in the 24-hr group. Histologic analysis revealed progressive damage to the arterial intima and media, as the time to repair was delayed. Delayed microsurgical arterial repairs of greater than 24 hr showed a poor patency rate, due to irreversible changes that occurred in the arterial intima and media.

Incidental Guyon's canal release during attempted endoscopic carpal tunnel release: an anatomical study and report of two cases.

Two patients were found to have a partial release of Guyon's canal after attempted endoscopic carpal tunnel release. This resulted in significant morbidity from ulnar nerve injury and required open neurolysis of the ulnar nerve and carpal tunnel release. In order to determine how this error could be made, we performed an endoscopic carpal tunnel release on two cadaveric specimens with subsequent dissection, and found that Guyon's canal could be entered with relative ease through the standard portals. If, however, one is aware of this potential complication, uses the ulnar bursa overlying the flexor tendons as a guide, and makes a positive identification of the transverse fibers of the transverse carpal ligament, this mistake can be avoided.

Prosthetic silicone scaphoid strains: effects of intercarpal fusions.

To assess stress shielding by partial intercarpal fusion, strains within a silicon scaphoid prosthesis were measured in five fresh upper extremities while the wrist was moved through a functional range of motion before and after capitate-lunate and capitate-hamate-lunate-triquetral intercarpal fusions. Capitate-lunate fusions resulted in an overall 18.4% reduction in compressive strains and a 10.8% reduction in tensile strains. Capitate-hamate-lunate-triquetral fusions reduced compressive strains by 28.5% and tensile strains by 26.3%. Radially deviated positions and positions of extension produced no reduction in strains with the partial fusions. Modest strain shielding can be obtained with partial intercarpal fusions. The effect, however, is position dependent, and whether this degree of strain shielding can reduce the incidence of particulate synovitis remains unknown.

Extraperiosteal toe phalanx transfer for congenital aphalangia: refinement of technique.

Toe phalanges with attached periosteum can be transferred to hands with congenital aphalangia, constructing rudimentary digits with growth potential. Using a volar technique, rather than the traditional dorsal method, allows stabilization of the constructed metacarpophalangeal joint and maximizes flexor function.

Congenital flexion deformities of the proximal interphalangeal joint in children: a subgroup of camptodactyly.

Severe flexion contractures of the proximal interphalangeal joint that are present at birth affect both sexes equally, often involve several digits of the same hand, and show no predilection for the small finger make up a distinct subgroup of the deformity known as camptodactyly. In this series, 20 digits with such severe flexion contractures were treated surgically. In eight digits, the flexor digitorum superficialis tendon was lengthened with or without release of contracted palmar structures. There was no improvement in these digits. In the other 12 digits, the extensor mechanism was realigned and augmented by release or transfer of the flexor digitorum superficialis tendon. All 12 of these digits had good (n = 10) to fair (n = 2) improvement in active and passive extension while retaining adequate flexion, although 9 still had some residual flexion contracture. In this type of camptodactyly, extensor mechanism anomalies appear to be the primary lesion.

Cerebral palsy. Management of the upper extremity.

Although only a small number of children with cerebral palsy have indications for surgical treatment of dynamic or structural upper-extremity deformities, orthopedic surgery does improve function and appearance of the involved hand, particularly in spastic hemiplegia. For further assessment of the patient after careful physical examination, myoneural nerve blocks and dynamic electromyography are useful. Physical and occupational therapists have an important role as crucial links among parents, patients, and physicians. Surgeons can try to prevent deformity with splints; however, their use in prevention of deformities of the hand has not been validated by scientific studies. Shoulder deformities can be managed with myotomies, tendon transfers, and (if fixed) osteotomies; rarely is arthrodesis used. Elbow flexion and dynamic or fixed deformities greater than 60 degrees are treated by lengthening of the muscles and tendons. Pronation deformities of the forearm are managed by myotomies, lengthenings, and tendon transfers. Wrist flexion deformities can be corrected with tendon lengthenings and transfers. The best results have been obtained with transfer of the flexor carpi ulnaris to the extensor digitorum communis. Finger flexion deformities can be managed satisfactorily with Z-lengthenings of the flexor digitorum superficialis in the forearm; rarely is it necessary to lengthen the flexor digitorum profundus. For adduction deformity of the thumb, division of the proximal or distal insertions of the adductor pollicis and release of the first dorsal interosseus muscle from the first and second metacarpals are preferred.

Chronic wrist pain: indications for wrist arthroscopy.

Although arthroscopy represents a new and dynamic diagnostic technique for evaluating the wrist, specific indications for arthroscopic intervention in the wrist are not defined. To place this technique in perspective, we review our experience with 54 consecutive arthroscopies of the radiocarpal and midcarpal joints in 53 patients with chronic wrist pain. On the basis of this review, we believe arthroscopy is indicated for the diagnosis of wrist pain of longer than 3 months' duration. Defects of the triangular fibrocartilage and lesions of the articular cartilage, including loose bodies, are detectable and easily treated with wrist arthroscopy.

Laser Doppler monitoring of replants using a small prism probe.

Eighteen patients admitted to Duke University Medical Center for upper limb replantation or revascularization were studied. A small laser Doppler flow prism probe and a cutaneous temperature probe were attached to the distal pulp of replanted digits. Measurements were recorded hourly for the first 3 postoperative days. In the successful cases, the mean laser Doppler flow measurement was 1.76 units (lower 97% confidence limit 0.5 units) and the mean temperature was 34.1 degrees C (lower 97% confidence limit 32 degrees C). In 4 patients with vascular compromise, the laser Doppler flow correctly identified the problem. The reduced size of the new laser Doppler probe makes monitoring of distal pulp flow technically easier while maintaining accuracy.