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Roy Sanders

Publications and source records attributed to Roy Sanders.

At least 19 recordsLinked to original sources
PubMed2006

Intra-lesional injections of collagenase are ineffective in the treatment of keloid and hypertrophic scars.

The treatment of keloid and hypertrophic scars remains difficult. Enzymatic digestion of keloid scars has been previously proposed as an effective treatment strategy for reducing the volume of keloid scars. To test this, we administered intra-lesional injections of pure collagenase (between 600 and 4500 units for each scar) into the keloid and hypertrophic scars of seven human volunteers (five keloid and two hypertrophic scars). Five patients (three keloid and two hypertrophic) received more than one injection of collagenase. The treatment resulted in a temporary reduction in scar volume for three of the patients with keloid scars. However, scar volumes for these three patients returned to the same (or greater) levels after 6 months of follow-up. Treatment with collagenase produced no change in scar volume for the two patients with hypertrophic scar. Side effects were numerous and severe including; pain, swelling, blistering, ulceration and ecchymosis at the site of injection. One patient required admission to hospital for 48 h after the first injection. Maximum length of follow-up was 6 months. None of the seven patients completed the study and returned for final follow-up at 2 years. This pilot study suggests that treatment of keloid and hypertrophic scars with intra-lesional injections of collagenase is ineffective.

Adult↗
PubMed2006

An investigation to optimize angiogenesis within potential dermal replacements.

BACKGROUND: Acute and chronic wounds are costly and invariably expose significant structures. Surgical reconstruction causes donor-site morbidity, scarring, and the need for intensive care. Reconstruction using an artificial dermis avoids donor sites, but available collagen-based solutions are susceptible to poor take. Using an in vitro angiogenic assay, the authors investigated dermal matrices for potential inclusion in a second-generation proangiogenic synthetic dermal replacement. METHODS: Human placental endothelial cells were cocultured on Cytodex beads (Pharmacia Biotech) and plated in eight different extracellular matrix gels (collagen, fibrin, four glycosaminoglycans, vitronectin, and fibronectin), with or without stimulation from two soluble angiogenic factors. Three different cell lines were used, with 30 beads per condition. Cellular invasion into gels was calculated using Sigma Scan computer software, and statistical comparisons were made. RESULTS: The authors found that fibrin provided greatest stimulus for endothelial invasion, with invasion in fibrin inhibited by collagen in a concentration-dependent fashion. Invasion by alternative extracellular matrix components and soluble angiogenic factors was far less than that in fibrin. CONCLUSIONS: The authors identified that extracellular matrices can provide greater angiogenic potential than soluble angiogenic factors. Fibrin provided a better proangiogenic scaffold than collagen. This could well be used to encourage blood vessel ingress and eventual take of a second-generation proangiogenic synthetic dermal replacement.

Angiogenesis Inducing Agents↗
PubMed2005

Trochanteric nail insertion for the treatment of femoral shaft fractures.

OBJECTIVES: This study was designed to evaluate whether the use of a new femoral nail, specifically designed to be inserted through the greater trochanter, could eliminate the complications previously seen with insertion of straight nails through this entry portal for the treatment of femoral shaft fractures. DESIGN: Prospective, clinical trial. SETTING: Three level I trauma centers. PATIENTS: Sixty-one consecutive patients with femoral shaft fractures (50 closed and 11 open fractures) treated with antegrade nailing with insertion through the greater trochanter. INTERVENTION: All patients were treated in the supine position with a TAN nail (Trigen System, Smith & Nephew, Memphis, TN) inserted through the greater trochanter. MAIN OUTCOME MEASURE: Union, alignment, complications, and hip function. RESULTS: Forty-six of 57 (81%) surviving patients were available for follow-up at a minimum of 12 (range, 12-25) months. Union occurred in all but 1 fracture after the index procedure. No patient sustained iatrogenic fracture comminution, and there were no angular malunions. Pain was reported as slight in 6 patients and moderate in 2. Visual and videotaped gate analysis, performed on 24 patients, revealed symmetrical walking in 21. CONCLUSIONS: This study demonstrates that antegrade nailing of femoral shaft fractures with a specially designed nail inserted through a trochanteric starting point provides predictably high union rates and low rates of complications. Ease of entry and utility in patients with a large body habitus are advantages over conventional piriformis fossa entry techniques. Nailing through the greater trochanter with the patient supine is presently our treatment of choice for patients with femoral shaft fractures.

Adolescent↗
PubMed2005

Acute care surgery.

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Attitude of Health Personnel↗
PubMed2004

A staged protocol for soft tissue management in the treatment of complex pilon fractures.

OBJECTIVE: To determine whether open reduction and internal fixation of intra-articular pilon fractures using a staged treatment protocol results in minimal surgical wound complications. DESIGN: Retrospective. SETTING: Level 1 trauma center. PATIENTS/PARTICIPANTS: Between January 1991 and December 1996, 226 pilon fractures (AO types 43A-C) were treated, of which 108 were AO type 43C. Fifty-six fractures were included in a retrospective analysis of a treatment protocol. Injuries were divided into Group 1, thirty-four closed fractures, and Group II, twenty-two open fractures (three Gustilo Type 1, six Type II, eight Type IIIA, five Type IIIB). METHODS: The protocol consisted of immediate (within twenty-four hour) open reduction and internal fixation of the fibula when fractured, using a one-third tubular or 3.5-millimeter dynamic compression plate and application of an external fixator spanning the ankle joint. Patients with isolated injuries were discharged after initial stabilization and readmitted for the definitive reconstruction. Polytrauma patients remained hospitalized and were observed. Formal open reconstruction of the articular surface by plating was performed when soft tissue swelling had subsided. Complications were defined as wound problems requiring hospitalization. All affected limbs were then evaluated via chart and radiograph review, patient interviews, and physical examination until surgical wound healing was complete, for a minimum of twelve months. RESULTS: Group I (closed pilon): Follow-up was possible in twenty-nine out of thirty fractures (97 percent). Average time from external fixation to open reduction was 12.7 days. All wounds healed. None exhibited wound dehiscence or full thickness tissue necrosis requiring secondary soft tissue coverage postoperatively. Seventeen percent (five out of twenty-nine patients) had partial-thickness skin necrosis. All were treated with local wound care and oral antibiotics and healed uneventfully. There was one late complication (3.4 percent), a chronic draining sinus secondary to osteomyelitis, which resolved after fracture healing and metal removal. Group II (open pilon): Follow-up was possible in seventeen patients with nineteen fractures (86 percent). Average time from external fixation to formal reconstruction was fourteen days (range 4 to 31 days). By definition, all Gustilo Type IIIB fractures required flap coverage for the injury. Two patients experienced partial-thickness wound necrosis. These were treated with local wound care and antibiotics. All surgical wounds healed. There were two complications (10.5 percent), both deep infections. One Type I open fracture developed wound dehiscence and osteomyelitis requiring multiple debridements, intravenous antibiotics, subsequent removal of hardware, and re-application of external fixator to cure the infection. One Type IIIA open fracture of the distal tibia and calcaneus developed osteomyelitis and required a below-knee amputation. CONCLUSION: Based on our data, it appears that the historically high rates of infection associated with open reduction and internal fixation of pilon fractures may be due to attempts at immediate fixation through swollen, compromised soft tissues. When a staged procedure is performed with initial restoration of fibula length and tibial external fixation, soft tissue stabilization is possible. Once soft tissue swelling has significantly diminished, anatomic reduction and internal fixation can then be performed semi-electively with only minimal wound problems. This is evidenced by the lack of skin grafts, rotation flaps, or free tissue transfers in our series. This technique appears to be effective in closed and open fractures alike.

Adult↗
PubMed2004

Open reduction and stable fixation of isolated, displaced talar neck and body fractures.

BACKGROUND: The purpose of this retrospective review was to evaluate the long-term results of surgical treatment of isolated, displaced talar neck and/or body fractures with stable internal fixation. METHODS: The study included twenty-five patients with a total of twenty-six displaced fractures isolated to the talus that had been treated with open reduction and stable internal fixation and followed for a minimum of forty-eight months after the injury. The final follow-up examination included standard radiographs, computed tomography, and a clinical evaluation. Variables that were analyzed included wound type, fracture type, Hawkins type, comminution, timing of the surgical intervention, surgical approach, quality of fracture reduction, Hawkins sign, osteonecrosis, union, time to union, posttraumatic arthritis, and the AOFAS scores including subscores (pain, function, and alignment). RESULTS: The average duration of follow-up was seventy-four months. Surgical intervention resulted in sixteen fractures with an anatomic reduction, five with a nearly anatomic reduction, and five with a poor reduction. All eight noncomminuted fractures were anatomically reduced. The overall union rate was 88%. All closed, displaced talar neck fractures healed, regardless of the time delay until surgical intervention. Posttraumatic arthritis of the subtalar joint was the most common finding and was seen in all patients, sixteen of whom had involvement of more than one joint. Osteonecrosis was a common finding, seen after thirteen of the twenty-six fractures overall and after six of the seven open fractures. CONCLUSIONS: Open reduction and internal fixation is recommended for the treatment of displaced talar neck and/or body fractures. A delay in surgical fixation does not appear to affect the outcome, union, or prevalence of osteonecrosis. Posttraumatic arthritis is a more common complication than osteonecrosis following operative treatment. Patients with a displaced fracture of the talus should be counseled that posttraumatic arthritis and chronic pain are expected outcomes even after anatomic reduction and stable fixation. This is especially true following open fractures.

Adult↗
PubMed2003

Mapping of vascular endothelium in the human flexor digitorum profundus tendon.

PURPOSE: Previous techniques to delineate the human flexor digitorum profundus (FDP) vasculature have been innovative but potentially imprecise, resulting in uncertainty as to the existence of avascular zones in the flexor tendon. We aimed to use a novel immunohistochemical technique to determine more accurately the vasculature of the human flexor tendon. METHODS: Thirty fresh cadaveric human FDP tendons were harvested, fixed, wax embedded, sectioned, and stained using the anti-CD31 monoclonal antibody to allow vessel visualization. Vessel numbers and vascularity density ratios were determined by computed image analysis. RESULTS: Vessel density ratios varied with anatomic location, with a decrease between the A2 and A4 pulleys. There also was variation in vascularity ratios in the anteroposterior plane, with the palmar surface of the tendons having a lower vessel density. CONCLUSIONS: We have shown that although areas of low vascularity exist on the palmar aspect of the tendon, there are no truly avascular zones.

Endothelium, Vascular↗
PubMed2003

Sunscreens inadequately protect against ultraviolet-A-induced free radicals in skin: implications for skin aging and melanoma?

Sunscreens are employed to mitigate the adverse effects of sunlight on skin but are primarily designed to prevent ultraviolet-B-associated burning and damage. The increasingly recognized role of ultraviolet A in aging, and possibly melanoma, highlights the need to include ultraviolet A screens; however, validation remains difficult. We have used a novel method to establish the efficacy of sunscreens, by measuring ultraviolet-A-induced free-radical production (thought to contribute towards ultraviolet-A-related aging and malignant change). Electron spin resonance spectroscopy was used to detect free radicals directly in human Caucasian skin during irradiation with levels of ultraviolet comparable to solar intensities. Using this system the protection afforded by three high factor sunscreens (sun protection factor 20+) that claim ultraviolet A protection was examined. Each sunscreen behaved similarly: at recommended application levels (> or = 2 mg per cm2) the ultraviolet-induced free radicals were reduced by only about 55%, and by about 45% at 0.5-1.5 mg per cm (0.5 mg per cm2 reported for common usage). A "free-radical protection factor" calculated on the basis of these results was only 2 at the recommended application level, which contrasts strongly with the erythema-based sun protection factors (mainly indicative of ultraviolet B protection) quoted by the manufacturers (20+). The disparity between these protection factors suggests that prolonged sunbathing (encouraged by use of these creams) would disproportionately increase exposure to ultraviolet A and consequently the risk of ultraviolet-A-related skin damage.

Free Radicals↗
PubMed2003

Use of oncogene expression as an independent prognostic marker for primary melanoma.

For 25 years, the Breslow depth of primary tumors has remained the most accurate prognostic test of survival for primary melanoma. However a number of studies have indicated that outcome for intermediate-thickness melanomas (0.75-2.49 mm) is often at variance with that predicted by the Breslow depth. This study investigated c-myc oncogene expression in 92 primary tumors of intermediate thickness using flow cytometry. Oncoprotein expression was detected in 87 tumors (95%) with a median positivity of 48% (range, 0%-96%). Survival analysis performed using the Kaplan-Meier method revealed a significant association between oncoprotein positivity and clinical outcome (p < 0.01, log-rank test). Multifactorial analysis of survival using Cox's proportional hazards model revealed c-myc oncoprotein to be an independent prognostic marker more accurate than all other clinicopathological parameters including the Breslow depth (chi(2) = 9.68, p< 0.01). Estimation of c-myc oncoprotein is therefore recommended as a powerful prognostic marker for intermediate-thickness primary melanoma.

Biomarkers, Tumor↗
PubMed2002

Minimal versus maximal plate fixation techniques of the ulna: the biomechanical effect of number of screws and plate length.

OBJECTIVE: To test the hypothesis that longer plates with the minimum number of screws provide equivalent or superior strength of fixation to standard compression plating using the maximum number of screws. DESIGN: Prospective analysis of biomechanical data was performed. SETTING: In vitro experimentation. INTERVENTIONS: A reproducible osteotomy was made in formalin-fixed ulnae. The osteotomies were stabilized employing six-, eight-, or ten-hole plates with two screws in the outermost holes and two screws in the innermost holes, and compared to stabilization with a six-hole plate with six screws. MAIN OUTCOME MEASURE: Four-point mechanical testing to failure was performed in both apex-dorsal (tension-band) or medial-lateral bending modes. Load-displacement curves were obtained. RESULTS: All of the longer plates with the minimum number of screws were stronger than the six-hole plate with six screws when tested in the medial-lateral and the tension-band mode. The eight-hole plate with four screws, however, was statistically inseparable from the fully loaded six-hole plate. There was no statistical difference between any of the configurations in regard to the stiffness of the fixation. CONCLUSIONS: In a cadaveric ulnar osteotomy model stripped of soft tissue, the number of screws is less important than the length of the plate in providing bending strength to the construct.

Bone Plates↗
PubMed2002

Factors influencing the decision to amputate or reconstruct after high-energy lower extremity trauma.

BACKGROUND: Factors thought to influence the decision for limb salvage include injury severity, physiologic reserve of the patient, and characteristics of the patient and their support system. METHODS: Eligible patients were between the ages of 16 and 69 with Gustilo type IIIB and IIIC tibial fractures, dysvascular limbs resulting from trauma, type IIIB ankle fractures, or severe open midfoot or hindfoot injuries. Data collected at enrollment relevant to the decision-making process included injury characteristics and its treatment, and the nature and severity of other injuries. Logistic regression and stepwise modeling were used to determine the effect of each covariate on the variable salvage/ amputation. RESULTS: Of 527 patients included in the analysis, 408 left the hospital with a salvaged limb. Of the 119 amputations performed, 55 were immediate and 64 were delayed. The multivariate analysis confirmed the bivariate analysis: all injury characteristics remained significant predictors of limb status with the exception of bone loss; and soft tissue injury and absence of plantar sensation were the most important factors in accounting for model validity. CONCLUSION: Soft tissue injury severity has the greatest impact on decision making regarding limb salvage versus amputation.

Adolescent↗
PubMed2002

The SOOF lift: its role in correcting midfacial and lower facial asymmetry in patients with partial facial palsy.

Subperiosteal face lifting has gained wide acceptance in aesthetic surgical practice. It may also have a role to play in patients with partial facial palsy. These patients demonstrate poor static position of the mouth but maintain some degree of facial movement. This study examined the role of subperiosteal facial suspension as an alternative treatment modality in this patient group. In this series, five patients with varying degrees of partial facial palsy underwent subperiosteal face lifting, including sub-orbicularis oculi fat elevation via a temporal, lower lid, and buccal approach, thereby mobilizing and elevating and suspending the zygomaticus major and levator labii superioris muscles on the facial skeleton. An attempt was made to categorize the patients according to overall House-Brackmann score. It was not possible to precisely classify the patients by this method, although the approximate scores were two patients scoring 3, two patients scoring 4, and one patient scoring 5. To overcome inconsistencies with this method, the degree of static and dynamic asymmetry of the mouth and also the excursion of the mouth were graded separately. Four patients with mild to moderate dynamic and static asymmetry (House-Brackmann score of approximately 3 and 4) who maintained excellent or good excursion of the mouth achieved excellent or good results. One patient with poor excursion and severe partial facial palsy (House-Brackmann score of 5) was improved but remained markedly asymmetric (follow-up, 4 months to 1 year). Subperiosteal face lifting is a useful therapeutic modality for management of selected patients with mild partial facial palsy. These patients demonstrate asymmetric static position but maintain some degree of muscle excursion. Patients with severe facial palsies with poor muscle excursion continue to require muscle transfer or sling procedures. The authors hope that long-term follow-up will confirm the sustained effect of midfacial suspension in this selected patient group.

Adipose Tissue↗
PubMed2002

Transcalcaneal talonavicular dislocation.

BACKGROUND: The combination of dorsal dislocation of the navicular from the talus and an associated comminuted fracture of the calcaneus (transcalcaneal talonavicular dislocation) is an unusual and severe injury. Six cases have been described previously. The purposes of this study were to report the prevalence of this injury and the variations in injury pattern and to characterize methods of treatment and patient outcomes. METHODS: Eight patients with nine cases of transcalcaneal talonavicular dislocation were treated by the senior author between January 1, 1990, and February 28, 1998. The comminuted fracture of the calcaneus was apparently caused by plantar flexion of the talus through the anterior portion of the calcaneus. There were five open Grade-III injuries and three associated lacerations of the posterior tibial artery. After initial provisional stabilization of the hindfoot and management of the soft tissues, all injuries were treated with delayed open reduction and internal fixation of the calcaneus and fusion of the subtalar joint. At the last follow-up examination, the outcomes were rated with the Maryland foot score, the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot rating score, and the Creighton-Nebraska score for all patients who had not had an amputation. RESULTS: The duration of follow-up ranged from 1.1 to eight years. Chronic osteomyelitis developed in four patients, and three of them ultimately had an amputation. The Creighton-Nebraska scores for the remaining six feet ranged from 33 to 92 points, with only one having a good or excellent result. Five of the six patients had a limp, difficulty with shoe wear, limitation with regard to walking, and moderate pain. CONCLUSIONS: Transcalcaneal talonavicular dislocation is a severe injury that often leads to osteomyelitis and amputation. Patients who do not lose the leg as a result of uncontrolled infection should be counseled to expect severe functional limitations and/or chronic pain.

Adult↗
PubMedDate not supplied

Compressed-air power tools in orthopaedic surgery: exhaust air is a potential source of contamination.

OBJECTIVES: To determine if the exhaust from surgical compressed-air power tools contains bacteria and if the exhaust leads to contamination of sterile surfaces. DESIGN: Bacteriologic study of orthopaedic power tools. SETTING: Level I trauma center operative theater. PATIENTS/PARTICIPANTS: None. INTERVENTION: Part I. Exhaust from two sterile compact air drills was sampled directly at the exhaust port. Part II. Exhaust from the drills was directed at sterile agar plates from varying distances. The agar plates represented sterile surfaces within the operative field. Part III. Control cultures. A battery-powered drill was operated over open agar plates in similar fashion as the compressed-air drills. Agar plates left open in the operative theater served as controls to rule out atmospheric contamination. Random cultures were taken from agar plates, gloves, drills, and hoses. MAIN OUTCOME MEASUREMENT: Incidence of positive cultures. RESULTS: In Part I, all filters from both compressed-air drill exhausts were culture negative ( = 0.008). In Part II, the incidence of positive cultures for air drills number one and number two was 73% and 82%, respectively. The most commonly encountered organisms were, coagulase-negative Staphylococcus, and Micrococcus species. All control cultures from agar plates, battery-powered drill, gloves, and hoses were negative ( < 0.01). CONCLUSIONS: Exhaust from compressed-air power tools in orthopaedic surgery may contribute to the dissemination of bacteria onto the surgical field. We do not recommend the use of compressed-air power tools that do not have a contained exhaust.

Air Microbiology↗
PubMedDate not supplied

Trochanteric versus piriformis entry portal for the treatment of femoral shaft fractures.

OBJECTIVES: The purpose of this study was to compare results of femoral shaft fracture treatment with nailing through the greater trochanter to nailing through the piriformis fossa with nails specifically designed for each starting point. DESIGN: Prospective cohort study. SETTING: Four level 1 trauma centers. PATIENTS: One-hundred and eight patients treated by 1 of 4 surgeons for a femoral shaft or subtrochanteric fracture with antegrade nailing between January 2001 and April 2003 were included. Four patients who expired early in the postoperative period and 13 with insufficient follow-up were excluded from analysis. INTERVENTION: Patients were treated with either nailing through a greater trochanter starting point with the Trigen TAN nail (GT group) (n = 38) or through a piriformis fossa starting point with the Trigen FAN nail (PF group) (n = 53). OUTCOME MEASURES: Operative time, fluoroscopy time, fracture alignment, fracture healing, complications, and functional outcome based on the lower-extremity measure (LEM). RESULTS: Thirty-seven of the 38 fractures from the GT group and 52 of the 53 fractures from the PF group healed after the index procedure. One patient from the GT group had external rotation malalignment of 12 degrees. There were no other malalignments or iatrogenic fracture comminution. There were 2 infectious complications, 1 from each group. The average operative time was 75 minutes for piriformis insertion using the FAN nail and 62 minutes for trochanteric insertion using the TAN nail (P = 0.08). The average fluoroscopy time was 61% greater for the PF group (153 seconds) than for the GT group (95 seconds) (P < 0.05). These differences were magnified in patients who were obese (body mass index > 30) where the operative time was 30% greater (P < 0.05) and the fluoroscopy time was 73% higher in the PF group (P < 0.02). Patients from both groups had a similar initial decline and subsequent improvement in function over time (P > 0.05). CONCLUSIONS: A femoral nail specially designed for trochanteric insertion resulted in equally high union rates, equally low complication rates, and functional results similar to conventional antegrade femoral nailing through the piriformis fossa. The greater trochanter entry portal coupled with an appropriately designed nail represents a rational alternative for antegrade femoral nailing with the benefit of decreased fluoroscopy time and decreased operative time in patients who are obese.

Adolescent↗