Biomechanical properties of Achilles tendon in diabetic vs. non-diabetic patients.

BACKGROUND/OBJECTIVES: Structural and functional impairments of the Achilles tendon in diabetic patients has the potential to contribute to ulcer formation through altered foot mechanics. This study aimed to examine the biomechanical and histopathological alterations in Achilles tendon specimens from diabetic vs. non-diabetic individuals. MATERIALS AND METHODS: 42 Achilles tendon samples obtained from patients treated with below-knee or above-knee amputation for chronic diabetic foot ulcers (n=21) or for non-diabetic conditions (n=21) were included. A tensile test was performed for each tendon and a stress vs. strain graft was obtained to calculate following biomechanical parameters: elasticity (Young modulus), load, stiffness, toughness, energy, strain, elongation and tenacity. Groups were also compared with regard to histopathological findings (inflammatory cell infiltration, collagen organization, and degeneration). RESULTS: Non-diabetic tendons exhibited a superior biomechanical profile over diabetic tendons with regard to the following biochemical parameters: elasticity, maximum load, stiffness, toughness, load, energy, strain and elongation at break point, tenacity, and strain at automatic load drop (p<0.05 for all comparisons). Diabetic tendons had mild impairment of collagen organization and focal collagen degeneration, whereas neither diabetic nor non-diabetic tendons had inflammatory cell infiltration. CONCLUSION: The structural and functional alterations associated with diabetes adversely affect the biomechanical properties of the Achilles tendon, potentially acting together with neuropathy and ischemia in the development of diabetic foot ulcers.

Results of treatment of the extensive volar wrist lacerations: 'the spaghetti wrist'.

'Spaghetti wrist' describes a volar wrist laceration in which at least 10 structures, inclusive of tendons, at least one major nerve and usually one major vessel are divided. This retrospective study, was performed between January 1990 and December 1995 at the Department of Orthopaedic and Traumatology of Erciyes University Medical School. The outcome of 21 patients who sustained simultaneous laceration of the median and ulnar nerves as well as flexor tendons at the wrist is described. The mean follow-up was 6.4 years. The flexor tendons were assessed using criteria from Lister et al. Vascular status was assessed clinically. Ulnar and median nerve repair results at the final control were assessed according to Seddon's criteria. Furthermore, the ulnar nerve was assessed according to the power of the first dorsal interosseous muscle, and the median nerve assessed by the function of abductor pollicis brevis and sensory function modality. Primary nerve repair yielded satisfactory results, the median nerve repair achieving a better outcome than the ulnar nerve. Most patients regained a functional range of wrist movement at the final control.

The effect of melatonin on plasma oxidant-antioxidant skeletal muscle reperfusion injury in rats.

We investigated the effects of melatonin administration on skeletal muscle ischaemia-reperfusion injury (IRI) by assessing plasma malondialdehyde (MDA), superoxide dismutase (SOD), total glutathione (GSSH), glutathione peroxidase (GPX) and myeloperoxidase (MPO) concentrations. Male Sprague-Dawley rats (n = 32) were randomized into four groups: group 1 served as time controls; group 2 were the test animals; group 3 received melatonin (30 mg/kg) intraperitoneally prior to the induction of ischaemia; and group 4 received melatonin (30 mg/kg) intraperitoneally prior to the reperfusion period. Administration of melatonin prior to reperfusion significantly decreased the elevated MDA concentration caused by IRI, and significantly elevated GSSH concentrations, which had been reduced by IRI. Ischaemia-reperfusion injury significantly increased activities of GPX, SOD and MPO, and melatonin administration reversed this effect. In conclusion, a pharmacological dose of melatonin showed significant protective effects against IRI by decreasing lipid peroxidation, MPO, SOD and GPX enzyme activities and regulating glutathione content.

Flexor tendon repair in zone 2 followed by early active mobilization.

The results following primary and delayed primary repair in zone 2 flexor tendon injuries were evaluated prospectively in 88 fingers of 71 patients using two different early postoperative mobilization programmes. In 33 patients, the Kleinert rubber band passive flexion method was used. In the remaining 38 patients, the early active mobilization programme was used. All patients were reviewed 1 year after operation and the results assessed by the Strickland criteria. During this evaluation maximum grip strength was also measured. The results were excellent or good in 78% of digits and mean grip strength was 84% of the uninjured hand in the Kleinert rubber band passive flexion group. In the early active mobilization group, excellent or good results were achieved in 85% of the digits and the mean grip strength was 90% of the uninjured hand. There were two early ruptures in each group.

The callotasis method of limb lengthening.

Limb lengthening by the callotasis technique of De Bastiani and use of the Orthofix external fixator was performed on 25 femurs and tibias of 23 patients between June 1989 and March 1995 in our clinic. Twenty femoral and five tibial segments were lengthened. Simultaneous lengthening of the femur and tibia was performed in two limbs. The mean duration of follow-up was 35.4 months (range, 12 to 81 months). Age at surgery ranged from 9 to 25 years (16.4 years on average). Poliomyelitis was the most common cause (69.6%) of the leg length discrepancy. The maximal achieved lengthening was 8 cm and the shortest 4 cm, with an average of 5.11 cm (13.6% of original bone length). The mean healing index was 38.6 days/cm; the complication rate was 36%. We conclude that limb lengthening by the De Bastiani method is a satisfactory procedure for pediatric and adult patients with moderate limb-length discrepancies.

The chondrogenic potential of free autogenous periosteal and fascial grafts for biological resurfacing of major full-thickness defects in joint surfaces (an experimental investigation in the rabbit).

In the present study, 40 rabbits were used, 30 of them for the experiment and 10 as controls. Full layer defects of 7-14 mm which were produced on knee joint cartilage were repaired with free autogenous periosteal and fascial grafts. The defects were made on the weight bearing areas of the medial condyles of the femurs of rabbits. The full layer periosteal grafts which were taken from the upper parts of the anterior tibia of 15 rabbits were located so that the combium layer faced the joint, and sutured to synovial membrane with 6.0 vicryl. The defects of the other rabbits were covered with fascial grafts obtained from fascia lata and were sutured to synovial membrane with 6.0 vicryl. No grafting was performed on the 10 rabbits in the control group after production of defects. The rabbits were immobilized for two hours postoperatively, and then allowed to be active. The rabbits in the experimental group were sacrificed in the third, sixth and ninth weeks respectively, and the rabbits of the control group were sacrificed in the ninth week. The distal femurs of 40 rabbits were removed and examined both macroscopically and histologically. The collagen phenotype was determined biochemically. When the assessments were made, it was noticed that the joint faces of the rabbits which were repaired with periosteal grafts were smooth, a tissue resembling hyaline joint cartilage had developed, and the synthesis of collagen of type II increased. On the other hand, the joint faces of the rabbits which were repaired with fascial grafts were not smooth, immature cartilage had with fibrous tissue developed, and the synthesis of type II collagen accounted for 50 per cent. The joint faces of the control group were course and covered with fibrous tissue, and the collagen synthesized was type I. According to these findings, we suggest that the biological repair of joint cartilage defects is possible with free autogenous periosteal grafts.

One-stage treatment of congenital dislocation of the hip in older children.

We reviewed the results of a primary one-stage combined operation in 47 patients (55 hips) who were > or = 4 years and had congenital dislocation of the hip. At a mean follow-up of 7.5 years (2-16 years), 67% of the whole series had good or excellent clinical results, and 65% were good or excellent radiologically. Avascular necrosis occurred in four patients, and redislocation also occurred in four patients. We concluded that most of the children who are > or = 4 years and who have congenital dislocation of the hip can successfully be treated with an extensive one-stage operation consisting of open reduction combined with innominate osteotomy and femoral varus, derotation, and shortening osteotomy.

Femoral shaft fractures in children treated by closed reduction and early spica cast with incorporated supracondylar Kirschner wires: a long-term follow-up results.

38 children between 1 and 10 years of age with femoral shaft fractures were treated by closed reduction and early spica cast with incorporated supracondylar Kirschner wires and followed up prospectively. Overrides of maximum 15 mm, medial and anterior angulations less than 15 degrees and lateral angulation up to 5 degrees were considered acceptable. Posterior angulation and malrotation were not accepted. Of the 38 children examined at a mean of 65.6 months (range, 58-80 months) after fracture, none had any residual skeletal deformity and joint stiffness. At long-term follow-up, maximal shortening was 11 mm and overgrowth was 6 mm. The only factor associated with unacceptable shortening was shortening > 15 mm at the time of spica cast application. We believe that close follow-up during the first 3 weeks after cast application is important in order to achieve an acceptable final outcome. On the other hand this method of treatment is simple, safe and effective. It dramatically decreases hospital stay and cost of treatment and allows rapid return of the patients to their family environment.