Biomedical subjects

Thomas E Trumble

Publications and source records attributed to Thomas E Trumble.

14 recordsLinked to original sources

PubMed2006

Idiopathic avascular necrosis of the scaphoid: Preiser's disease.

Preiser's disease, or idiopathic avascular necrosis of the scaphoid, is a rare, albeit often debilitating, condition. Although unknown, the etiology is probably multifactorial, with biomechanical or anatomical variations leading to an "at risk" scaphoid. Most commonly the diagnosis is made with the use of plain radiographs, but one should not hesitate to use MRI for both confirming the diagnosis and evaluating the stage of the disease. Current treatment algorithms are not standardized, and many scaphoids degenerate to a point that a salvage procedure is required. The authors attempt a revascularization procedure if the disease is caught early and the scaphoid has not yet gone on to collapse and degenerate. We save our salvage procedures for advanced cases with periscaphoid arthritis.

Humans↗

PubMed2006

Comparison of pullout button versus suture anchor for zone I flexor tendon repair.

PURPOSE: To evaluate the clinical outcome after repair of zone I flexor tendon injuries using either the pullout button technique or suture anchors placed in the distal phalanx. METHODS: Between 1998 and 2002 we treated 26 consecutive zone I flexor tendon injuries. Thirteen patients had repairs from 1998 to 2000 using a modified pullout button technique (group A) and 13 patients had repair using suture anchors placed in the distal phalanx (group B). Patient characteristics were similar for both groups. The same postoperative flexor tendon rehabilitation protocol and follow-up schedule were used for both groups. Evaluation included range of motion, sensibility and grip strength, failure, complications, and return to work. The Student t test was used to determine significant differences. RESULTS: All patients completed 1 year of follow-up evaluation. There were 2 infections in group A that resolved with oral antibiotics and no infections in group B. There were no tendon repair failures and no repeat surgeries in either group. At final follow-up evaluation there were no statistically significant differences for the following end points: sensibility (Semmes-Weinstein monofilament testing and 2-point discrimination), active range of motion (at the proximal interphalangeal joint, distal interphalangeal joint, or their combined motion), flexion contracture (at the proximal interphalangeal joint, distal interphalangeal joint, or their combined contracture), and grip strength (injured tendon as a percent of the contralateral uninjured tendon). The suture anchor group had a statistically significant improvement for time to return to work. CONCLUSIONS: There was no significant difference in the clinical outcome after flexor tendon repair using either suture anchors or the pullout button technique. A significant improvement was found for time to return to work for repairs using the suture anchor technique. Flexor tendon repair can be achieved using suture anchors placed in the distal phalanx, thereby avoiding the potential morbidity associated with the pullout button technique. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic, Level III.

Adolescent↗

PubMed2006

A biomechanic comparison of an internal radiocarpal-spanning 2.4-mm locking plate and external fixation in a model of distal radius fractures.

PURPOSE: To compare the biomechanic stability of distal radius fracture fixation with a new internal radiocarpal-spanning 2.4-mm locking plate, which acts as an internal distal radius fixator, versus a standard distal radius external fixator. The number of locking screws necessary for adequate fracture fixation was also assessed. METHODS: Ten cadaveric specimens were mounted in a loading fixture with cables attached to the 2 flexor and 3 extensor wrist tendons. A 1-cm osteotomy was created to simulate an unstable distal radius fracture. The radiocarpal-spanning locking plate was fixed to the radius and index metacarpal with 4 screws proximally and 4 distally. The specimen was incrementally loaded through the tendons. Motion at the fracture site was determined. Screws were sequentially removed from the construct, the specimen was again incrementally loaded, and fracture motion was measured. The fixation was then changed to an external fixator, and the loading tests were repeated. RESULTS: Fracture fixation with the radiocarpal-spanning 2.4-mm locking plate was significantly more stable with 4 screws proximally and 4 screws distally (4 x 4) and with the 3 x 3 configuration than with the external fixator in both flexion and extension. The 4 x 4 screw configuration was not significantly different from the 3 x 3 screw configuration. The 4 x 4 screw configuration was significantly more stable than the 2 x 2 and 1 x 1 screw configurations in both flexion and extension. All internal fixator configurations and the external fixator showed more fracture displacement at increasingly higher loads. CONCLUSIONS: Fracture fixation with the new internal radiocarpal-spanning 2.4-mm locking plate is more stable than with a standard distal radius external fixator. Only three 2.4-mm locking screws proximally and three 2.4-mm locking screws distally are required for adequate fixation of the locking spanning plate.

Aged↗

PubMed2006

Open and arthroscopic treatment of perilunate injuries.

UNLABELLED: Carpal dislocations are rare and complex injuries. Nearly every combination of radiocarpal and intercarpal dislocation has been described, but few fit neatly into a particular pattern or classification scheme. The injury may be subtle clinically and radiographically, and the diagnosis is frequently delayed. Prompt recognition, accurate reduction, and stable temporary internal fixation all contribute to improved outcomes. Internal fixation techniques depend on the pathology imparted on the carpus. Open reduction, arthroscopic, and fluoroscopically aided percutaneous techniques can be used to successfully treat carpal dislocations. We report our experiences treating perilunate injuries. LEVEL OF EVIDENCE: Level V (expert opinion).

Algorithms↗

PubMed2005

Treatment of distal radius fractures with intrafocal (kapandji) pinning and supplemental skeletal stabilization.

The technique of intrafocal pinning was originally described by Kapandji. This technique, along with the addition of supplemental external or internal bridging fixation, can be performed quickly with minimal soft tissue damage. This technique is indicated for the treatment of unstable extra-articular or minimally displaced intra-articular fractures of the distal radius. Studies demonstrate that young patients with displaced extra-articular distal radius fractures and minimal comminution can be treated by percutaneous intrafocal pin fixation alone, whereas, patients over 55 years of age and younger patients with comminution involving two or more surfaces of the radial metaphysis (or > 50% of the metaphyseal diameter) require bridging fixation besides percutaneous pin fixation. The use of this technique achieves the goal of surgical treatment of distal radius fractures: restoration of hand and wrist function through the restoration of alignment and articular surface congruity.

Bone Nails↗

PubMed2005

Trans-scaphoid perilunate fracture dislocations: results of screw fixation of the scaphoid and lunotriquetral repair with a dorsal approach.

PURPOSE: To review the clinical and radiographic outcome of dorsal trans-scaphoid perilunate fracture-dislocations treated with screw fixation of the scaphoid and repair of the lunotriquetral ligament with bone anchors. METHODS: Twenty-five patients treated over an 11-year period for dorsal trans-scaphoid perilunate fracture-dislocations were reviewed retrospectively at a mean of 44.3 months. The mean age of the patients was 28.6 years, and 22 patients were men. Delay to surgery was 3.5 days. Five scaphoids had bone grafting from the distal radius. Six patients developed carpal tunnel syndrome requiring release. The functional outcome was determined by comparing the range of motion of the injured extremity with the uninjured extremity, grip strength, ability to return to pre-injury employment, and overall patient satisfaction. Radiographic evaluation comprised time to scaphoid union, any changes in the lunotriquetral interval, development of a volar intercalated segmental instability pattern, and any development of arthritis over time. RESULTS: Total range of motion achieved was 91% of the uninjured wrist and grip strength was 80%. Average extension was 54 degrees with an average flexion of 60 degrees . Ulnar deviation was 23 degrees with radial deviation averaging 18 degrees . The average supination was 76 degrees and the average pronation was 76 degrees . All scaphoids united primarily. The average time to union of the scaphoid was 16 weeks. For those scaphoids with bone grafting the union time was an average of 18.4 weeks. The average postreduction lunotriquetral gap was 1.8 +/- 0.4 mm. The average lunotriquetral gap at the last follow-up evaluation was 1.9 +/- 0.6 mm. None of the patients developed a volar intercalated segmental instability deformity. All but 2 patients returned to their pre-injury occupation. All patients, however, returned to some type of employment. Complications included 1 superficial pin track infection that resolved with removal of the pin and a short course of oral antibiotics. CONCLUSIONS: A dorsal approach to the wrist provides adequate exposure for reduction of carpal bones, internal fixation of the scaphoid, and lunotriquetral repair. Although perilunate fracture-dislocations are challenging problems to treat, all of the patients had acceptable pain relief and achieved sufficient range of motion and strength to return to gainful employment.

Adolescent↗

PubMed2005

Overcoming peripheral nerve gap defects using an intact nerve bridge in a rabbit model.

This study investigated the intact nerve bridge technique for overcoming peripheral nerve gap defects in a rabbit model. To create the intact nerve bridge, a 1-cm segment of the peroneal nerve is resected leaving a gap defect. The proximal and distal peroneal nerve stumps are sutured 1 cm apart, in an end-to-side fashion, to the intact tibial nerve epineurium. Four experimental groups were used (n = 10): primary repair of resected segment; intact nerve bridge; nerve autograft; and gap in situ control. Evaluation after 12 weeks included measurement of isometric muscle contraction force, axonal counting, wet muscle weights, and histologic examination. The results of this study support two main conclusions, in a rabbit model: (a) regenerating axons can use the epineurium of an intact nerve to bridge a gap defect; (b) there is no significant difference in the functional recovery between standard nerve autografts and the intact nerve bridge technique.

Animals↗

PubMed2004

A cadaver model to evaluate the accuracy and reproducibility of plain radiograph step and gap measurements for intra-articular fracture of the distal radius.

PURPOSE: The purpose of this study was to determine the accuracy and reproducibility of intra-articular step-off and gap displacements measured on plain radiographs using a standard cadaver model. METHODS: Twenty-two physicians, in a blinded randomized fashion using a standard technique, examined the radiographs of 12 unique combinations of step and gap displacement created by a 3-part intra-articular osteotomy of the distal radius. Observer accuracy, inter- and intraobserver agreement, and tolerance limits were calculated. RESULTS: The results of this study suggest that observers, independent of skill level, may measure step-off and gap displacements accurately to within .62 +/- .53 mm (95% confidence interval = .59-65). The accuracy of measurement was influenced by the quality of the radiograph. Intraclass correlation coefficient scores showed "substantial" (.78) to "almost perfect" (.81) inter- and intraobserver agreement. CONCLUSIONS: These data can aid in the interpretation of clinical studies of acute distal radius fractures that are based on plain radiography.

Cadaver↗

PubMed2004

Regeneration along intact nerves using nerve growth factor and ciliary neurotrophic factor.

The purpose of this investigation was to evaluate the ability of a specific growth factor combination, nerve growth factor (NGF) and ciliary neurotrophic factor (CNTF), to enhance peripheral nerve regeneration. Eight groups of eight Sprague-Dawley rats underwent repair of a nerve gap defect: Group A (immediate repair), Group B (intact nerve bridge), Group C (nerve autograft), Group D (gap in situ), Group E (NGF + CNTF), Group F (NGF), Group G (CNTF), and Group H (saline). Twelve weeks after surgery, analysis included the measurement of the isometric force of muscle contraction for the tibialis anterior muscle and tissue harvesting for both quantitative and qualitative analysis. When evaluating muscle contraction force, there was no statistically significant difference among the experimental groups receiving a growth factor injection and the normal saline control group. The hypothesis of this study was that peripheral nerve regeneration could be enhanced by the combination of NGF and CNTF. The evidence does not support this hypothesis.

Analysis of Variance↗

PubMed2003

Biomechanical function of the distal radioulnar and ulnocarpal wrist ligaments.

PURPOSE: This study was designed to provide quantitative information concerning the functions of the ligaments that stabilize the distal radioulnar joint (DRUJ). This joint permits the radius to rotate around a nearly fixed ulna allowing supination and pronation of the hand. Understanding their function is important in developing procedures for reconstruction. METHODS: Using a ligament tension transducer that hooked under the center of the ligament and deflected it laterally while measuring the force required, we determined the tensions in 6 ligaments in 9 cadaver arms in pronation and supination of the hand. These ligaments included those of the DRUJ: palmar distal radioulnar ligament (PDRUL) and dorsal distal radioulnar ligament (DDRUL); and the ulnocarpal joint ligaments: ulnolunate ligament (ULL), ulnotriquetral ligament (UTL), and the ulnocarpal collateral ligament (UCCL), which includes the subsheath of the extensor carpi ulnaris, and the dorsal ulnocarpal ligament (DUCL). RESULTS: For the ligaments of the DRUJ in supination, the mean tension in the PDRUL (2.6 N) was greater than that of the DDRUL (0.8 N), whereas in pronation the mean tension in the PDRUL (1.1 N) was less than that of the DDRUL (1.7 N). For the ulnocarpal ligaments in supination, the ligament tensions in the ULL, UTL, and the UCCL were significantly greater than the same ligaments with the forearm pronated. The DUCL tension remained unchanged throughout supination and pronation. CONCLUSIONS: In supination of the forearm all ligaments except for the DDRUL had equivalent tensions, indicating their role in stabilizing the joint to this motion. In pronation ligament tensions generally were lower but were distributed over all 6 ligaments tested. DUCL tension was equivalent in both supination and pronation, unlike the other ligaments that had greater tensions in supination.

Carpal Bones↗

PubMed2003

Central placement of the screw in simulated fractures of the scaphoid waist: a biomechanical study.

BACKGROUND: Recent reports on internal fixation of acute fractures of the scaphoid waist have demonstrated higher rates of central placement of the screw when cannulated screws were used than when noncannulated screws were used. This cadaveric study was designed to determine whether central placement in the proximal fragment of the scaphoid offers a biomechanical advantage. METHODS: Eleven matched pairs of scaphoids were removed from fresh cadaveric wrists. Each scaphoid was placed in a custom manufactured jig that was used to create reproducible central and eccentric positioning of the guidewire. Then a linear osteotomy was made followed by placement of a Herbert-Whipple cannulated screw to fix the osteotomy. The specimen was then potted in a holder with use of polymethylmethacrylate with a Kirschner wire passed through the proximal end of the scaphoid and placed into a fixture with a pneumatically driven plunger resting on the surface of the distal pole. The load acting through the plunger was measured with use of a load-cell, and its excursion was measured with use of a linear variable differential transformer. Stiffness, load at 2 mm of displacement, load at failure, and mechanism of failure were measured, and the two groups were compared with regard to stiffness and strength. RESULTS: Central placement of the screw in the proximal fragment of the scaphoid had superior results compared with those after eccentric positioning of the screw. Fixation with central placement of the screw demonstrated 43% greater stiffness (12.7 N per mm compared with 8.9 N per mm; p < 0.01), 113% greater load at 2 mm of displacement (126 N compared with 59.1 N; p < 0.01), and 39% greater load at failure (712 N compared with 513 N; p > 0.05). CONCLUSIONS AND CLINICAL RELEVANCE: Central placement of the screw in the proximal fragment of the scaphoid offers a biomechanical advantage in the internal fixation of an osteotomy of the scaphoid waist. Clinical efforts and techniques that facilitate central placement of the screw in the fixation of fractures of the scaphoid waist should be encouraged.

Biomechanical Phenomena↗

PubMed2002

Wrist fractures.

The benefits of a well-reduced and well-healed wrist fracture are predictable. This knowledge has prompted the development of myriad treatment methods and fixation devices. The choice of open versus closed reduction and the devices used to maintain that reduction could most often be determined with a well-defined and reproducible closed reduction maneuver. With this maneuver, the integrity of the critical volar ulnar corner of the radius is determined as is articular stepoff, metaphyseal comminution, and distal radionular joint (DRUJ) stability. Reconstruction of the subluxed or dislocated DRUJ starts with the reduction of the radius, frequently obviating the need to address fractures involving the ulnar head and styloid. Most importantly, the results of treatment reflect surgical decision over the fixation method.

Bone Nails↗

PubMed2002

Single-portal endoscopic carpal tunnel release compared with open release : a prospective, randomized trial.

BACKGROUND: Carpal tunnel syndrome is a common condition causing hand pain and numbness. Endoscopic carpal tunnel release has been demonstrated to reduce recovery time, although previous studies have raised concerns about an increased rate of complications. The purpose of this prospective, randomized study was to compare open carpal tunnel release with single-portal endoscopic carpal tunnel release. METHODS: A prospective, randomized, multicenter center study was performed on 192 hands in 147 patients. The open method was performed in ninety-five hands in seventy-two patients, and the endoscopic method was performed in ninety-seven hands in seventy-five patients. All of the patients had clinical signs or symptoms and electrodiagnostic findings consistent with carpal tunnel syndrome and had not responded to, or had refused, nonoperative management. Follow-up evaluations with use of validated outcome instruments and quantitative measurements of grip strength, pinch strength, and hand dexterity were performed at two, four, eight, twelve, twenty-six, and fifty-two weeks after the surgery. Complications were identified. The cost of the procedures and the time until return to work were recorded and compared between the groups. RESULTS: During the first three months after surgery, the patients treated with the endoscopic method had better Carpal Tunnel Syndrome Symptom Severity Scores, better Carpal Tunnel Syndrome Functional Status Scores, and better subjective satisfaction scores. During the first three months after surgery, they also had significantly (p < 0.05) greater grip strength, pinch strength, and hand dexterity. The open technique resulted in greater scar tenderness during the first three months after surgery as well as a longer time until the patients could return to work (median, thirty-eight days compared with eighteen days after the endoscopic release). No technical problems with respect to nerve, tendon, or artery injuries were noted in either group. There was no significant difference in the rate of complications or the cost of surgery between the two groups. CONCLUSION: Good clinical outcomes and patient satisfaction are achieved more quickly when the endoscopic method of carpal tunnel release is used. Single-portal endoscopic surgery is a safe and effective method of treating carpal tunnel syndrome.

Adult↗

PubMedDate not supplied

Management of scaphoid nonunions.

Scaphoid nonunions result in a predictable pattern of wrist arthrosis. To minimize the incidence of arthrosis, the goal of treatment should be consolidation of the fracture with the scaphoid in anatomic alignment. Computed tomography and magnetic resonance imaging scans can aid evaluation of carpal collapse, scaphoid collapse, scaphoid nonunion, bone loss, and detection of osteonecrosis. Nonunion of the scaphoid waist may result in a humpback deformity, increasing the chances of further collapse and arthrosis. This collapse deformity must be approached volarly with an intercalary bone graft and internal fixation. A dorsal approach to proximal scaphoid nonunions allows easier access for removing the necrotic bone from the proximal pole and applying accurate screw or pin fixation. Vascularized bone graft is recommended to manage scaphoid nonunions with osteonecrosis.

Bone Transplantation↗