[Supracondylar process and supratrochlearforamen of the humerus: a case report and a review of the literature]

The conundrum of olecranon aperture and its relation to the distal end of the humerus in a modern Indian population: An anatomical and surgical perspective

PURPOSE

We aimed to clarify the morphology of the olecranon aperture (OA) of the humerus with its relationship to the distal end of the humerus (epicondylar width) and the width of the medullary canal.

METHODS

In total, 156 dry adult humeri were examined for the presence of OA. When present, we reported their shape, measured transverse (TD) and vertical diameter (VD), the distance from its medial border to the tip of medial epicondyle (D1), lateral border to the tip of lateral epicondyle (D2) and lower border to the tip of trochlea (D3). The epicondylar width (EW) and the width of the medullary canal were also measured in all the humeri.

RESULTS

OA was reported in 32 humeri (20.6%) with left side predominance, translucent septum in 35.8%, and opaque septum in 43.6%. The most typical shape noted was oval. On right side, mean VD and TD was 4.30±0.54mm and 5.85±0.45mm, respectively, whereas on left, these value were 4.21±0.56mm and 5.64±0.43mm, respectively. The mean of D1, D2 and D3 was 25.86±0.43mm, 26.50±0.28mm and 15.07±0.53mm on right and 24.80±0.41mm, 26.84±0.21mm and 15.81±0.31mm on left with significant difference (P<0.05). The medullary canal was significantly smaller in humeri with OA.

CONCLUSION

Topographic location of OA may have possible role in determining safe zone for retrograde nailing in supracondylar humeral fractures. Since OA has a direct relation to the size of the intramedullary canal, it is crucial during preoperative planning and choosing an adequate surgical approach involving lower segment of humerus.

Anatomical and Radiological Aspects of the Supratrochlear Foramen in Brazilians

INTRODUCTION

The supratrochlear foramen is an anatomic variation of great clinical and anthropologic interest. Although many studies addressed this subject in different ethnic groups, there are no studies regarding Brazilians.

AIM

To verify the incidence and morphometric measures of the supratrochlear foramen in Brazilian humeri.

MATERIALS AND METHODS

A total of 330 dry humeri were analysed and divided in three groups: bones presenting the supratrochlear foramen (Group 1), bones displaying a translucent foramen (Group 2) and humeri without the foramen (Group 3). The aperture was measured with a digital vernier caliper. Radiographic pictures with different incidences were taken.

RESULTS

Our analysis showed that 22.5% of humeri belonged in Group 1, 41.2% in Group 2, and 36.3% in Group 3. The mean vertical diameter and the mean horizontal diameter of the supratrochlear foramen on the left side were 2.779±2.050 mm and 2.332±1.23 mm, respectively. The mean vertical diameter and the mean horizontal diameter of the foramen on the right side were 2.778±2.197 mm, and 2.365±1.396 mm, respectively. The student's t-test showed that there was no significant difference regarding the size of the foramen between both sides. The best X-ray machine setup was 50 kilo voltage and 0.08 milliamperage per second, associated with a slight increase in the distance of the x-ray tube.

CONCLUSION

The aperture seems to be the key point during the pre-operative planning of intramedullary fixation, since it has direct relation to the size of the intramedullary canal, thus, being an entity of clinical, anatomical, anthropological, radiological, and surgical interest.

Supratrochlear foramen of the humerus: an anatomico-radiological study with clinical implications

BACKGROUND

The supratrochlear foramen (STF) of the humerus has been a neglected entity in standard anatomy and orthopaedics text-books. The knowledge of the presence of STF in a humerus may be important for preoperative planning for treatment of supracondylar fractures. The presence of STF may also result in erroneous interpretation of radiographs.

METHODS

The STF was studied in detail in 384 (220 left side and 164 right side) human dried humeri of unknown sex and age. The topographical anatomy of the STF was studied in detail, morphometric measurements were taken, and the specimens were photographed. The humerus was also taken for radiological assessment of the STF and supratrochlear septum.

RESULTS

Out of the 384 bones studied, 132 cases (34.3%) showed the presence of STF. The STF was oval, round, and triangular in shape in 123, 7, and 2 cases, respectively. The mean length of the transverse diameter for supratrochlear foramen was 6.55 mm and 5.99 mm on the left and right sides, respectively. The mean length of the vertical diameter for STF was 4.85 mm and 3.81 mm on the left and right sides, respectively. Most of the bones that had no STF showed a translucency of septum, in 56.7% of the bones.

CONCLUSIONS

The results of our study show that STF is more common on the right side, with the oval shape being more common. The respective sides did not exhibit any statistical significant differences. Presence of STF may be important for anthropological, clinical, and academic purpose.