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Bo Sanderhoff Olsen

Publications and source records attributed to Bo Sanderhoff Olsen.

8 recordsLinked to original sources

[Elbow arthroplasty].

Each year, about 80 elbow arthroplasties are performed in Denmark. Approximately two thirds are done due to rheumatoid arthritis, the others due to comminuted fractures of the elbow, especially in elderly patients. The prosthesis is fixed with or without bone cement, and there are two different types of elbow prostheses: linked, in which the humerus and ulna are connected by a sloppy hinge, and non-linked, in which stability is dependent on the soft tissues of the elbow. Good pain relief can be expected, but the range of motion will usually be permanently affected.

Adult↗

Wrist stability after experimental traumatic triangular fibrocartilage complex lesions.

PURPOSE: The aim of this study was to evaluate changes in stability of the wrist after experimental traumatic triangular fibrocartilage complex lesions. METHODS: Sixteen cadaver wrist specimens were included: 8 were fixed in neutral rotation of the forearm, 4 in maximal supination, and 4 in maximal pronation. The specimens were tested in a multiangle and torque measuring instrument. First the intact specimen was tested, second a dorsal arthrotomy was performed, and the third test was with 1 of 4 different experimental lesions according to Palmer's classification of traumatic triangular fibrocartilage complex lesions (1A-1D). Forced radioulnar deviation and internal/external rotation were recorded with a load of 0.75 Nm in the interval -60 degrees to +60 degrees of flexion. RESULTS: We found the 1C lesion to be highly significantly related to wrist stability. Forced radioulnar deviation and forced internal/external rotation were altered significantly in 35 degrees of wrist extension. The other lesions did not alter the stability of the wrist significantly and the rotation of the forearm had no influence on the outcome. CONCLUSIONS: The 1A lesion does not alter significantly wrist stability and hence the common treatment by a two-third excision of the central part of the disk will not affect wrist stability. A 1C lesion alters significantly the stability of the wrist. At 35 degrees of wrist extension forced radioulnar deviation and forced internal/external rotation were altered significantly; this might be used in a clinical test for a 1C lesion. The rotation of the forearm has no influence on the outcome.

Aged↗

Elbow joint laxity after experimental radial head excision and lateral collateral ligament rupture: efficacy of prosthetic replacement and ligament repair.

The objectives of this experimental study were to investigate the effect of radial head excision and lateral collateral ligament (LCL) division on elbow joint laxity and to determine the efficacy of radial head prosthetic replacement and LCL repair. Valgus, varus, internal rotation, and external rotation of the ulna were measured during passive flexion-extension and application of a 0.75-Nm torque in 6 intact cadaveric elbows and after (1) either excision of the radial head or division of the LCL, (2) removal of both constraints, (3) isolated radial head prosthetic replacement, (4) isolated LCL repair, and (5) radial head replacement combined with LCL repair. Isolated radial head excision increased varus (mean, 4.8 degrees) and external rotatory laxity (mean, 7.1 degrees), as did isolated LCL division (mean, 14.1 degrees for varus; mean, 14.7 degrees for external rotation). After removal of both constraints, varus and external rotatory laxities were increased by 19.0 degrees and 20.1 degrees, respectively, compared with the intact specimens. Isolated radial head replacement reduced mean varus laxity to 14.6 degrees and mean external rotatory laxity to 14.8 degrees. Isolated LCL repair normalized varus laxity but resulted in a 2.9 degrees increase in external rotatory laxity. The combined procedures restored laxity completely. The radial head is a constraint to varus and external rotation in the elbow joint, functioning by maintaining tension in the LCL. Still, removal of both constraints induces severe laxity, and in this case, prosthetic replacement may substitute for the constraining capacity of the native radial head. The combination of LCL repair and radial head replacement restores laxity completely, but an isolated LCL repair performs almost as well, probably by compensating for the ligamentous tension lost from radial head excision.

Adult↗

Capitellocondylar total elbow replacement in late-stage rheumatoid arthritis.

Between 1994 and 2000, 51 capitellocondylar elbow replacements were inserted in 41 patients. All patients had late-stage rheumatoid arthritis. The mean age at operation was 56 years (range, 25-78 years). There were 12 men and 29 women. At follow-up, 6 patients had died of unrelated causes with the implant in situ and without radiographic loosening, and 1 patient was lost to follow-up. The remaining 43 elbows in 34 patients were followed up clinically and radiographically at a mean of 6.9 years (range, 26-119 months). Relief of pain was complete in 91% of the surviving elbows, and in 9%, there was only mild pain. Pain-free range of motion at follow-up was significantly improved. Flexion increased a mean of 43 degrees ; extension, 16 degrees ; supination, 24 degrees and pronation, 26 degrees . Of the elbows, 7 underwent revision, 3 because of deep infection, 1 for aseptic loosening, and 3 because of instability. Other complications included 2 maltracking elbows, 2 triceps tendon ruptures, 2 cases of operative olecranon bursitis, and 2 ulnar nerve palsies. One elbow showed radiolucent lines of more than 1 mm in the circumference of the ulnar component; none of the other elbows showed any signs of progressive radiographic loosening. At a mean follow-up of 6.9 years, a functional prosthesis was retained in 82.7% of the elbows, and the mean survival of the implant was 8.6 years (95% CI, 7.8-9.5 years).

Adult↗

Long-term results with the Kudo type 3 total elbow arthroplasty.

From 1992 to 1993, 17 elbows were replaced with the unlinked Kudo type 3 total elbow arthroplasty in 16 patients with arthritic joint destruction. Of these elbows, 8 were available for clinical examination after a mean of 9.5 years. Of the 17 elbow implants, 5 were revised: 2 because of loosening of the ulnar component, 1 because of dislocation, 1 because of a periprosthetic fracture, and 1 because of a late deep infection. At 9.5 years' follow-up, 67.9% of the prostheses had survived, and the mean survival of the implant was 8.7 years (95% confidence interval, 7.5-10 years). In this study, we observed high rates of progressive valgus tilting of the ulnar component. This valgus tilting is of major concern because it provides more stress to a smaller area on the polyethylene. It may, therefore, cause an increased degree of polyethylene wear and, thereby, reduce the final implant survival rate.

Adult↗

Functional anatomy of the lateral collateral ligament complex of the elbow: configuration of Y and its role.

A previous anatomic study has revealed that the lateral collateral ligament (LCL) complex of the elbow has a Y-shaped configuration, which consists of a superior, an anterior, and a posterior band. The LCL complex, including the annular ligament, functions as a 3-dimensional (3D) Y-shaped structure. On the basis of this concept, joint laxity after transection of the anterior band was studied in 5 normal, fresh-frozen cadaver elbows with a 3D kinematic testing apparatus. Cutting the anterior band produced significant laxity to varus torque with a mean 5.9 degree at 10 degree of elbow flexion and caused significant laxity to torque in external rotation with a mean 8.5 degree at 40 degree of flexion. No significant laxity was observed during application of valgus or internal rotational torque. Further transection of the posterior band resulted in gross instability with dislocation of the ulnohumeral joint. The laxity occurring after severance of the anterior band suggests that these fibers play a role in preservation of elbow stability against varus and external rotational torque. These results indicate that the LCL functions as a complex with a Y structure and not as an isolated linear ligament. A concept of conjoint point is hypothesized for the function of the LCL complex to restrain posterolateral rotatory instability.

Aged↗

Radiohumeral stability to forced translation: an experimental analysis of the bony constraint.

Radiohumeral stability to forced translation was experimentally analyzed in 8 osteocartilaginous joint preparations. The joints were dislocated in 8 centrifugal directions at 12 different combinations of joint flexion and rotation while a constant joint compression force of 23 N was applied. Stability was measured as the maximum resistance to translation. On average, the specimens could resist a transverse force of 16.4 N (range, 13.0-19.1 N). Stability was greater in some directions than in others. Rotating the joint changed the direction at which stability was greatest, whereas joint flexion did not. In supination, the greatest stability was observed for anteromedial dislocations, in neutral rotation for posteromedial dislocations, and in pronation for posterolateral dislocations. The findings from this study indicate systematic variations in wall height around the radial head concavity as well as individual variations in joint constraint. This may have implications for the treatment of conditions involving radiohumeral joint dislocation.

Cadaver↗