Biomedical subjects

V J Sammarco

Publications and source records attributed to V J Sammarco.

5 recordsLinked to original sources

PubMed2001

Stability and fixation techniques in first metatarsal osteotomies.

Osteotomy of the first metatarsal is a common procedure for correction of hallucal disease. Metatarsals are unique in that they are the only long bones in the human body that support load perpendicular to their longitudinal axis during standing. Thus, osteotomy of the first metatarsal may be complicated by loss of fixation, resulting in nonunion or malunion. The authors review the forces that must be resisted by the osteotomy of the first metatarsal as postoperative weight bearing is initiated, and explore the principles of osteotomy geometry and different fixation techniques to maximize stability of the final construct and to minimize the risk of displacement.

Biomechanical Phenomena↗

PubMed2001

Complications of lateral ankle ligament reconstruction.

Complications after ankle ligament reconstruction are infrequent, but present significant challenges to the treating orthopaedist. Local wound problems and nerve injuries may cause difficulty in the early postoperative period. Recurrent instability may be attributable to failure of the operation, poor rehabilitation, reinjury, or unrecognized predisposing factors. Postoperative stiffness of the subtalar and ankle joints frequently is reported after anatomic and nonanatomic tenodesis procedures and may cause significant morbidity. The current author reviews reported complications and treatment options in failed lateral ankle ligament surgery.

Ankle Joint↗

PubMed2000

Os acromiale: frequency, anatomy, and clinical implications.

BACKGROUND: Os acromiale is present when the anterior portion of the acromion has one or more separate ossicles. Its frequency has been documented, in radiographic and anatomical studies, to be between 1 and 15 percent. Reports of os acromiale associated with subacromial pathology have been cited to imply that this entity is a cause of subacromial impingement; however, no study has demonstrated an increased frequency of os acromiale in patients with shoulder pain compared with the frequency in the general population. Inconsistencies in the literature concerning anatomy, development, and frequency prompted the current anatomical study. The purpose of this study was to better define the frequency and anatomy of os acromiale in the general population. METHODS: Two thousand three hundred and sixty-seven scapular bones from 1198 human skeletons from the Hamann-Todd Osteological Collection were studied for evidence of os acromiale. The sample consisted of specimens from 1033 men and 165 women, 843 of whom had been white and 355, black. The mean age of the individuals at the time of death was 44.7 years (range, eighteen to eighty-nine years). The frequency of os acromiale was noted, and the specimens were measured. RESULTS: There were 128 cases of os acromiale in ninety-six (8.0 percent) of the 1198 skeletons, and the condition was bilateral in thirty-two (33.3 percent) of the ninety-six skeletons. In twenty cases, the free fragment had been lost but it was assumed that a fragment had been present because the acromion was truncated. Os acromiale was more frequent in blacks than in whites (13.2 compared with 5.8 percent; p < 0.001) and in men than in women (8.5 compared with 4.9 percent; p = 0.09). The mean proportional length of the free fragment was 0.42 compared with the overall length of the acromion. Care was taken to differentiate os acromiale from a normal immature acromion. Six skeletons demonstrated persistent acromial apophyses. All six cases were bilateral; seven fragments were fusing, and five were free. The oldest age at which a persistent normal apophysis was found was twenty-one years. The frequency of os acromiale in specimens from individuals who had been less than twenty-two years old was not significantly different from that in the remainder of the collection (p = 0.74). Twenty-one scapulae had a distinct circumferential line that was suggestive of an acromial joint, but the distal and proximal portions were solidly fused. However, the findings on plain axillary radiographs of sixteen of these specimens were indistinguishable from those of specimens with os acromiale. CONCLUSIONS: An anatomical study, performed to better define the frequency and anatomy of os acromiale in the general population, showed that fused os acromiale, which has not been described previously, might be mistaken for a free ossicle in the clinical setting.

Acromion↗

PubMed1997

Human articular cartilage storage in cell culture medium: guidelines for storage of fresh osteochondral allografts.

The viability of transplanted articular cartilage is one of the determinants of outcome following the transplantation of osteochondral allografts. Disappointing results from cryopreservation have led to the practice of fresh transplantation of articular segments, especially for posttraumatic defects. To date, no studies have demonstrated in vitro viability rates for refrigerated human cartilage awaiting transplantation. This study evaluates the effects of storage on the viability of human chondrocytes using cell culture medium. Human articular cartilage obtained from notchplasties was stored for up to 48 hours in cell culture medium. Radioactive 35S-sulfate uptake was determined at 0, 24, and 48 hours, as a measure of protein, synthesis, and chondrocyte viability. Specimens were stored at 4 degrees C in culture medium. Results showed an average decrease in 35S-sulfate uptake of 0.8% at 24 hours and 6.4% at 48 hours, indicating a high level of chondrocyte viability after refrigeration. Because transplantation typically is performed within 24 hours of tissue harvest, it appears that nearly 100% of chondrocytes should survive fresh transplantation.

Cartilage, Articular↗

PubMed1993

Bunion correction using proximal Chevron osteotomy.

Fifty-one cases of moderate to severe bunion deformity with hallux valgus and metatarsus primus varus in 43 patients were treated by bunionectomy, proximal Chevron metatarsal osteotomy, lateral capsulotomy, adductor tenotomy, and lashing of first and second metatarsals together. The hallux valgus angle improved an average of 19 degrees from 33 degrees (mean) preoperatively to 14 degrees (mean) postoperatively. The intermetatarsal angle improved an average of 7.3 degrees from an average of 14 degrees preoperatively to an average of 6 degrees postoperatively. The position of the sesamoids was realigned to beneath the first metatarsal head and the metatarsal length remained essentially unchanged. Union occurred in 9 weeks (mean). No malunions occurred. Foot score profiles revealed a significant improvement in subjective evaluation from 69/100 preoperatively to 83/100 postoperatively with respect to pain, deformity, motion, disability, and cosmesis. Seventy-eight percent of patients had a good to excellent result. Improved subjective evaluations indicated that proximal Chevron osteotomy combined with bunionectomy, capsulotomy, tenotomy, and metatarsal lashing provides a reliable method with respect to stability, technical ease, low complication, and satisfactory surgical outcome for correction of moderate and severe bunion deformity, both as a primary and revision procedure.

Adolescent↗