Search PubMed⌕ Search

Biomedical subjects

K M Khan

Publications and source records attributed to K M Khan.

132 records · Page 8Linked to original sources
PubMedDate not supplied

Intercellular junctions in the differentiating rat otocyst.

Intercellular junctions between cells of the rat otocyst on the 12th day of gestation were studied using lanthanum tracer and freeze-fracture techniques. At the luminal surface, the intercellular space is closed by a series of tight junctions. Gap junctions are also present between cells both within and below the luminal junctional complex. The presence of tight and gap junctions at this early stage in the differentiating otocyst is probably essential for the development of a normally functioning adult ear.

Animals↗
PubMedDate not supplied

Open and arthroscopic patellar tenotomy for chronic patellar tendinopathy. A retrospective outcome study. Victorian Institute of Sport Tendon Study Group.

Chronic patellar tendinopathy often requires surgical treatment. We compared the outcomes in 25 subjects (29 tendons) who had had open patellar tenotomy and 23 subjects (25 tendons) who had had arthroscopic patellar tenotomy at a mean follow-up of 3.8 and 4.3 years, respectively. At follow-up, outcomes in the open and arthroscopic groups were as follows: 1) symptomatic benefit was seen in 81% of open and 96% of arthroscopic tenotomy patients, 2) sporting success was seen in 54% of open and 46% of arthroscopic tenotomy patients, 3) median time to return to preinjury level of activity was 10 months for open and 6 months for arthroscopic tenotomy patients, and 4) median Victorian Institute of Sport Assessment score at follow-up was 88 for open and 77 for arthroscopic tenotomy patients. There were no significant differences between groups for all outcomes. The appearance of the tendon on sonography remained abnormal in over 70% of subjects at follow-up, and sonographic appearance did not correlate with clinical outcome. Thus, arthroscopic patellar tenotomy was as successful as the traditional open procedure. Both procedures provided virtually all subjects with symptomatic benefit, but only about half the subjects who underwent either open or arthroscopic patellar tenotomy were competing at their former sporting level at follow-up.

Adolescent↗
PubMedDate not supplied

Outcome of surgery for chronic Achilles tendinopathy. A critical review.

Achilles tendinopathy is often treated surgically after failure of nonoperative management, but results are not uniformly excellent. We critically assessed the methods of 26 studies that reported surgical outcomes of patients with this condition. Using 10 previously published criteria, and blinded to study outcomes, we derived a "methodology score" (0 to 100) for each study. This score was highly reproducible (r = 0.99, P < 0.01). Scores were generally low concerning the type of study, subject selection process, and outcome measures, which indicates methods deficiency in the way the study was designed, performed, and analyzed. We found a negative correlation between reported success rate and overall methods scores (r = -0.53, P < 0.01), and a positive correlation between year of publication and overall methods score (r = 0.70, P < 0.01). Study methods may influence reported surgical outcome, and we suggest guidelines for improving study design in this area of clinical research. We acknowledge that study methods have improved over the course of the past 20 years.

Achilles Tendon↗
PubMedDate not supplied

Outcome of conservative and surgical management of navicular stress fracture in athletes. Eighty-six cases proven with computerized tomography.

Eighty-two athletes with 86 clinical navicular stress fractures, all imaged with computerized tomography, were followed for an average of 33 months (range, 6 to 108) after diagnosis. Initial treatment consisted of at least 6 weeks of nonweightbearing cast immobilization for 22 fractures, at least 6 weeks of limitation of activity with continued weightbearing for 34 fractures, and a period of less than 6 weeks of conservative treatment for another 19 fractures. Five patients attempted to continue playing sports. Six patients had immediate surgery. Nineteen of 22 patients (86%) who had initial non-weightbearing cast immobilization treatment returned to sports, compared with only 9 of 34 patients (26%) who initially continued weightbearing with limited activity (P < 0.001). After failure of the latter treatment, successful outcomes were seen for 6 of 7 patients (86%) treated with nonweightbearing cast immobilization, while 11 of 15 patients (73%) who had one surgical procedure were able to return to sports. These results indicate that nonweightbearing cast immobilization is the treatment of choice for navicular stress fractures. Also, this treatment compares favorably with surgical treatment for patients who present after failed weightbearing treatments. Computerized tomographic appearances of healing fractures do not necessarily mirror clinical union, and postimmobilization management should be monitored clinically.

Adolescent↗
PubMedDate not supplied

Bone geometric response to chronic disuse following stroke: a pQCT study.

OBJECTIVES: The objectives of this study were to 1) assess volumetric bone geometry and density at the distal radius of individuals with chronic stroke and 2) assess whether bone strength is associated with measures of muscle strength and impairment. MATERIAL AND METHODS: Cross-sectional study of bone and muscle parameters in 15 community-dwelling people living with the residual effects of a stroke (between 1 and 9 years post-incident stroke). RESULTS: The 4% site of the distal radius had significantly lower bone mineral content and density on the paretic side (p<0.006). There was a significant difference in pQCT measures of bone cortical density (p<0.03), area (p<0.05) and bone strength [Stress-Strain Index; SSI] (p<0.01) (lower on the paretic side) at the 30%. We found significant correlations between composite muscle strength score of the upper extremities and pQCT-generated bone strength. CONCLUSIONS: This cross-sectional study highlights lower bone strength on the paretic limb and an adaptive response to disuse.

Biomechanical Phenomena↗