OBJECTIVES

In elderly patients the temporary loss of function of the upper extremity due to immobilization for treatment of unstable proximal humeral fractures is a very disabling condition. Stable fixation of such fractures allowing immediate functional aftercare may contribute to early social reintegration in this group of patients. Aim of this study is to present the surgical technique of humeral blade plate fixation and the clinical and radiographic results after fixation of unstable surgical neck fractures with this implant followed by immediate functional treatment in patients older than 60 years.

Introduction: The osteotomy in shoulder arthroplasty is based on the assumption that the resected articular segment corresponds to a segment of a sphere oriented, identically, in inclination and retroversion to the original humeral head(1). A previous report has suggested that the traditional osteotomy technique performed along the antero-superior part of the anatomical neck does not accurately replicate inclination and retroversion of the humeral head(2). We hypothesize that a simulated osteotomy performed along the antero-inferior anatomical neck resects a portion of the humeral head similarly oriented to the original head in terms of inclination and retroversion, and, more closely matches head diameter and radius of curvature when compared to the traditional osteotomy approach.

Methods: Twenty-eight fresh frozen cadaveric full arms were dissected free of soft tissue. Lines, points and surfaces were identified on each specimen. A Microscribe digitizer was used to digitize the points and lines. Data were imported into Rhinoceros NURBS modelling software and graphically modelled. The following parameters were used to describe the humeral head geometry: the longitudinal and axial radii of curvature (RoC) of the articular surface; the inclination angle (ƒÑ) and retroversion angle (ƒÒ). To simulate the traditional osteotomy, a plane was constructed using points at the anterior portion of the anatomical neck. The new osteotomy plane was formed using points at the antero-inferior anatomical neck. Paired Student’s t-test was used to compare techniques.

Results: No differences were found between the axial RoC of the resected segment for the new technique (22.5mm) when compared to the original head (22.5mm); a difference was found for the old osteotomy technique (23.0mm). In the coronal plane, no differences were found for the RoC of both the new and traditional techniques when compared to the original head. The axial and coronal diameters of the osteotomized surface were significantly different for both techniques. However, the mean difference between the axial and coronal diameters for the new technique was 2.4mm and, for the traditional technique, 3.2mm. Significant differences in retroversion of the resected surface were found when the new osteotomy technique (24.5deg) and traditional technique (40.5deg) were compared to the original head (29.0deg). Further, significant differences in inclination were found, when the new osteotomy technique (129.5deg) and traditional technique (132.1deg) were compared to the original head inclination (136.9deg).

Discussion: This study found that an osteotomy performed along the anteroinferior part of the anatomical neck removes an articular segment that is more spherical than a segment removed by the traditional osteotomy approach. Although significantly different from the original head, the retroversion associated with the new technique more closely matches the anatomy when compared to the traditional technique. The new osteotomy decreased the inclination angle by 7 degrees. This finding is unlikely to be clinically relevant. Cadaveric studies will reveal the accuracy of an anatomical reconstruction using the novel osteotomy approach.

Introduction: Restoration of original humeral head geometry in shoulder arthroplasty is a necessary requirement and may have a bearing on the longevity of the implant. Modern, adaptable, prosthetic components are believed to allow restoration of the individual’s proximal humeral anatomy, provided a precise osteotomy of the humeral head at the level of the anatomical neck is performed. The osteotomy and reconstruction of the humeral head is based on the assumption that the resected articular segment corresponds to a segment of a sphere oriented, identically, in inclination and retroversion to the original humeral head. Resection, along the mid-anterior portion of the cartilage/calcar border, is understood to create a surface that enables a prosthetic component to be mounted, retroverted and inclinated to the same degree as the original head geometry. The objective of this study was to determine the degree of variation in humeral head retroversion relative to the superior and inferior borders of the proximal humeral articular surface.

Methods: Twenty-eight fresh frozen human cadaveric full arms were dissected free of soft tissue to expose the proximal humerus. The distal end of the humeral shaft was potted in PMMA and fixed rigidly in a custom–built jig. The following points and lines were identified and marked on each specimen:

the circumference of the anatomical neck;

A Microscribe 3D-X digitizer was used to digitize the points and lines. The data for each humerus were imported into Rhinoceros NURBS modelling software and graphically represented. The constructed graphical model was used to divide the articular portion of the humeral head into six equal sections in the axial plane. The retroversion angle, relative to the epicondyles, was calculated for each section.

Results: A linear decrease in retroversion angle was noted from the most superior to most inferior point on the proximal humeral articular surface. The retroversion angle was greatest at the level of the insertion of the supraspinatus tendon (34.2deg +/−13.7deg) and least at the inferior cartilage/calcar interface (24.3deg +/−10.2deg).

Discussion: Accurate recovery of humeral head geometry is a requirement in order to achieve good function. The variability in retroversion, as it relates to its point of measurement, may effect the accuracy of pre-operative assessment of a patient’s humeral head geometry as well as the osteotomy during shoulder arthroplasty, and, thus, may impact on joint range of motion and stability post-operatively. Further investigation is warranted.

Introduction and Aims: There is a clinical impression that rheumatoid involvement of the hand and wrist in black patients differs from white patients. The aim of this study was to look at the hand and wrist involvement in black patients and to compare it with the available series in white patients.

Method: The wrist and hand x-rays of 75 black patients with proven rheumatoid arthritis were used. The x-rays were classified according to the Larsen criteria. We also classified the wrist involvement according to the Stanley and Simmen classifications. We also looked at the extent of wrist involvement and the stability of the wrist.

Results: The Larsen score for the fingers was counted out of 100 – where each MP-joint and each PIP-joint, including the IP-joint of the thumb, counts five (5 x 20). The Larsen score for the left hand was 9,65 and for the right hand 10,32. The Larsen score for the wrist was counted out of five. It was 2,48 for the left wrist and 2,73 for the right wrist. According to the Stanley classification on the right side, 18 fell into the conservative group, 16 into the reconstructive group, 28 into the salvage group and 13 into the irretrievable group. In the Simmen classification on the right side, 23 were classified as normal, 14 as ankylosed, nine as osteo-arthritic and 29 as disintegrated. On the left side, 22 were classified as normal, 12 as ankylosed, 12 as osteo-arthritic and 29 as disintegrated.

Conclusion: Our conclusion is that rheumatoid arthritis involvement was more or less the same as reported in other series, but finger joint involvement was considerably less. This finding must influence surgical decision-making and also the results of drug trials, whenever black patients are involved.