Biomedical subjects

T Pevny

Publications and source records attributed to T Pevny.

7 recordsLinked to original sources

PubMed1998

Primary traumatic anterior shoulder dislocation in patients 40 years of age and older.

During three consecutive ski seasons (1991 to 1994), 125 patients 40 years of age and older without previous shoulder injuries or surgery sustained a traumatic first-time anterior shoulder dislocation. At a minimum of 2 years' follow-up, patients were contacted to determine long-term outcome and to identify factors leading to prolonged morbidity or the need for surgical intervention. Fifty-two patients were available for interview. A modified Rowe shoulder score showed 32 excellent, nine good, eight fair, and three poor results. Eighteen (35%) rotator cuff tears were subsequently identified, with only 11 (61%) of these patients obtaining an excellent or good outcome (P = .011). Of the 11 patients with a fair or poor result, seven (64%) had a rotator cuff tear. Of the 12 patients with isolated cuff tears, 84% had an excellent or good result when treated surgically, compared with 50% when treated nonsurgically. Our findings indicate that recurrence is not a frequent complication of traumatic anterior shoulder dislocation in this age-group (4%). However, prolonged morbidity secondary to rotator cuff tear is more prevalent than in a younger population. We believe early diagnosis of rotator cuff pathology by either magnetic resonance imaging (MRI) or arthrogram with subsequent surgical repair can lead to faster restoration of function and a better outcome in these select individuals.

Adult↗

PubMed1996

Early complications with external fixation of pediatric femoral shaft fractures.

A retrospective study of 27 pediatric patients with femoral shaft fractures treated by external fixation was made to identify complications and evaluate outcomes. The average age at the time of injury was 8 years, 9 months (range 5 years, 6 months to 13 years, 2 months). Sixteen fractures were isolated, and nine were associated with polytrauma. There was only one open fracture. Data obtained from chart review (n = 27), radiographs (n = 27), physical exam (n = 16), and questionnaire (n = 21) identified eight major complications (30%) in six patients and 29 minor complications (107%) in 20 patients. The major complications included two refractures, two fractures through pin sites, one postimmobilization supracondylar femoral fracture, one persistent pin-tract infection requiring early fixator removal, one malreduction, and one loss of reduction. Both the patient with malreduction and the one who lost reduction had > 10 degrees of varus deformity before adjustment of their frames. Five of the eight major complications (64%) were secondary to errors in operative technique or postoperative treatment. Only one major complication was noted among the 16 patients with isolated injuries. Of the patients with minor complications, 14 had pin-tract infections requiring oral antibiotics, five refused to go to school with the fixator in place, five were dissatisfied with scar appearance, and five had clinically insignificant malunions. A clinically insignificant malunion was considered to be angulation > or = 5 degrees varus or valgus or > or = 10 degrees procurvatum or recurvatum deformity that did not affect the patient's function. The minor complications were considered intrinsic to the procedure and difficult to avoid. Despite these problems, all patients with isolated injuries, except one with a slipped capital femoral epiphysis, had excellent function at the time of final review. If external fixation is chosen as the method of treatment for a pediatric femur fracture, careful attention must be paid to operative technique and postoperative treatment in order to minimize complications.

Adolescent↗

PubMed1996

Recurrent dislocation of the pisiform bone.

A 17-year-old man had chronic pain and recurrent radial dislocation of the pisiform bone following a fall on his outstretched arm. The bone was excised, along with a 3 x 4-mm osteocartilaginous fragment from the distal triquetrum. Pisotriquetral joint instability should be considered in the differential diagnosis of palmar-ulnar wrist pain.

Adolescent↗

PubMed1995

Ligamentous and tendinous support of the pisiform, anatomic and biomechanical study.

Twenty-five formalin preserved cadaveric wrists were dissected and the relationship of the piso-triquetral joint and its surrounding soft tissue structures were defined. An additional 4 fresh frozen wrists were examined in longitudinal and transverse sections. These anatomical studies showed the extensor retinaculum to have a complex insertion into the pisiform, flexor carpi ulnaris, fifth metacarpal, piso-metacarpal ligament, and the abductor digit minimi muscle. A capsulo-ligamentous structure on the medial aspect of the piso-triquetral joint was also identified. Bio-mechanical testing was performed on 12 fresh cadaver wrists and the results were compared to the anatomical findings to determine the contribution of surrounding soft tissue structures to piso-triquetral joint stability. Mechanical testing showed the soft tissues around the piso-triquetral joint to be strongest proximally and distally and weakest medially. Transection of the transverse carpal ligament resulted in increased lateral motion of the pisiform, but there was no significant decrease in stiffness. This study provides insight into the etiology of piso-triquetral joint instability and dysfunction.

Biomechanical Phenomena↗

PubMed1995

Ligamentous and tendinous support of the pisiform: anatomic and biomechanical study.

Twenty-five formalin-preserved cadaveric wrists were dissected and the relationship of the pisotriquetral joint (PTJ) and its surrounding soft tissue structures were defined. An additional 4 fresh frozen wrists were examined in longitudinal and transverse sections. These anatomical studies showed the extensor retinaculum to have a complex insertion into the pisiform, flexor carpi ulnaris, fifth metacarpal, pisometacarpal ligament, and the abductor digiti minimi muscle. A capsuloligamentous structure on the medial aspect of the pisotriquetral joint was also identified. Biomechanical testing was performed on 12 fresh cadaver wrists and the results were compared to the anatomical findings to determine the contribution of surrounding soft tissue structures to pisotriquetral joint stability. Mechanical testing showed the soft tissues around the pisotriquetral joint to be strongest proximally and distally and weakest medially. Transection of the transverse carpal ligament resulted in increased lateral motion of the pisiform, but there was no significant decrease in stiffness. This study provides insight into the etiology of pisotriquetral joint instability and dysfunction.

Biomechanical Phenomena↗

PubMed1994

Case report 876: Aneurysmal bone cyst of the patella.

A case of aneurysmal bone cyst of the patella in a 15-year-old woman was presented. An ABC occurring in a female patient is rare, and to our knowledge this is the first report in the literature. All other reports of patellar ABCs reported have occurred in young black men [2, 3]. The radiographic findings and clinical presentation were stressed since they are typical of all benign patellar tumors. Although radiographic findings are usually typical of patellar tumors, CT and MRI may be used for staging and standardization of operative treatment. MRI is also helpful for examining the integrity of the patellar tendon and quadriceps since many of these patients present with malfunction of the extensor mechanism [14].

Adolescent↗

PubMed1987

Stabilization of a reactive, electrophilic carcinogen, benzo[a]pyrene diol epoxide, by mammalian cells.

We have studied several features of the interactions of 7r,8t-dihydroxy-9t,10t-oxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE-I) with a DNA repair-proficient derivative of Chinese hamster ovary cells (CHO), AT3-2, and with a UV-light sensitive mutant, UVL-10, derived from AT3-2. Methods were developed for quantitating the amount of unhydrolysed BPDE-I associated with cells and for purifying DNA from cells under conditions where artificial labeling during preparation is minimized. In both cell types, about 30% of the BPDE-I added to a cell culture is rapidly taken up by the cells and is maintained in a cellular compartment in which the half-life of BPDE-I is about 10-fold longer than in aqueous medium. The kinetics of covalent binding to DNA were measured in both cell types and found to be described well by a single exponential process with a half-life of about 60 min. This is virtually identical to the half-life for intracellular hydrolysis of BPDE-I (57 min), consistent with the suggestion that this intracellular, relatively stable BPDE-I is responsible for binding.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗