Hans Clement

The influence of lateral and anterior angulation of the proximal ulna on the treatment of a Monteggia fracture: AN ANATOMICAL CADAVER STUDY

We have investigated the anatomy of the proximal part of the ulna to assess its influence on the use of plates in the management of fractures at this site. We examined 54 specimens from cadavers. The mean varus angulation in the proximal third was 17.5 degrees (11 degrees to 23 degrees ) and the mean anterior deviation 4.5 degrees (1 degrees to 14 degrees ). These variations must be considered when applying plates to the dorsal surface of the ulna for Monteggia-type fractures. A pre-operative radiograph of the contralateral elbow may also be of value.

Delayed hypopharyngeal and esophageal perforation after anterior spinal fusion: primary repair reinforced by pedicled pectoralis major flap.

Study Design. This report documents a case of delayed hypopharyngeal and esophageal perforation after anterior spinal fusion and reviews relevant literature. Objectives. Presentation of an alternative solution of primary repair and reinforcement of a delayed esophageal and hypopharyngeal perforation after anterior spinal fusion. Summary of Background Data. Anterior plating is generally used for stabilization after cervical spine trauma. Esophageal and hypopharyngeal perforation is a rare but potentially life-threatening complication due to mediastinitis with consecutive septic shock and multiorgan failure. Methods. Our patient was operated on after cervical trauma caused by car accident. The neurologic condition did not improve in the postoperative period. About 4 months later, the patient had increasing dysphagia as well as episodes of odynophagia. Flexible esophagoscopy showed a perforation of a part of the plate from the hypopharynx down to the proximal esophagus. Primary repair reinforced by a pedicled pectoralis major flap was done without complications. Results. Postoperative fluoroscopy as well as endoscopy showed no signs of perforation. Swallowing was possible without any further episodes of dysphagia or odynophagia. Neck movement was unconfined. Conclusions. Primary repair reinforced by pedicled pectoralis major flap has been shown to be an alternative in case of combined hypopharyngeal and esophageal perforation due to orthopedic spine stabilization. Advantage of the pectoralis major muscle flap is no functional loss of neck movement.

Morphometric Analysis of Lister's Tubercle and Its Consequences on Volar Plate Fixation of Distal Radius Fractures

PURPOSE The objective of this study was to measure the size and shape of Listers tubercle and the depth of the extensor pollicis longus (EPL) groove to assess the risk of injury to the EPL tendon when performing volar plating of distal radius fractures. METHODS The length and height of Listers tubercle and the depth of the EPL groove were measured in 100 cadavers. RESULTS The size of Listers tubercle varied from 2 to 6 mm (average, 3.6 mm) in height radial to the tubercle and from 6 to 26 mm (average, 18.3 mm) in length. The depth of the EPL groove varied from 1 to 5 mm (average, 2.8 mm), with 63% being greater than 2 mm in depth. The height between the depth of the groove and the tip of the tubercle varied between 4 and 10 mm (average, 7.1 mm). No correlation was found with gender or right-side or left-side specimens. CONCLUSIONS The individual and combined height of Listers tubercle and the depth of the EPL groove are considerable. This fact needs to be considered when performing volar plating of distal radius fractures because of the possibility that it might be difficult to determine precisely the presence and amount of past-pointing of the distal screws.

The influence of ultrasound guidance in the rate of success of acromioclavicular joint injection: an experimental study on human cadavers

BACKGROUND Injections of the acromioclavicular joint (ACJ) are performed routinely in patients with ACJ arthritis, both diagnostically and therapeutically. The aim of this prospective controlled study was to estimate the frequency of successful intra-articular ACJ injections with the aid of sonographic guidance versus non-guided ACJ injections. MATERIALS AND METHODS A total of 80 cadaveric ACJs were injected with a solution containing methylene blue and subsequently dissected to distinguish intra- from peri-articular injections. In 40 cases the joint was punctured with sonographic guidance, whereas 40 joints were injected in the control group without the aid of ultrasound. RESULTS The rate of successful intra-articular ACJ injection was 90% (36 of 40) in the guided group and 70% (28 of 40) in the non-guided group. Ultrasound was significantly more accurate for correct intra-articular needle placement (P = .025). DISCUSSION The use of ultrasound significantly improves the accuracy of ACJ injection.

Anatomical basis of the risk of radial nerve injury related to the technique of external fixation applied to the distal humerus

PurposeStabilization of humeral shaft and elbow fractures can be achieved with an external-fixator. Reports about nerve injuries associated with this procedure are rare in literature. Purpose of this anatomical study was to examine the relation of the radial nerve to distal humeral half pins.MethodsPercutaneous insertion of external-fixator half pins was performed in 20 upper limbs of 20 cadavers, according to established technique, laterally in the distal humerus.ResultsDissection of the upper limbs showed radial nerve injury in four of the 40 placed half pins. The proximal half pin impaled the nerve in one case and the distal half pin in three cases. Moreover the nerve was directly in contact with the pins in nine cases (five proximally, four distally).ConclusionsInsertion of external-fixator half pins in the distal humerus can easily injure the radial nerve. Thus we advocate a larger skin incision, blunt dissection to the lateral cortex of the humerus and retraction of soft tissue during half pin insertion.

Various Circular Arc Radii of the Distal Volar Radius and the Implications on Volar Plate Osteosynthesis

The purpose of this anatomical study was to explore the different circular arc radii of the distal volar radius and provide more detailed anatomic information that will further the understanding of volar plate osteosynthesis. The profiles of the volar distal radii of 100 cadaver specimens were measured with a common profile gauge. Profiles were copied onto paper and then matched to a best-fit circular arc template to determine the radius of curvature on the radial and ulnar sides of the distal volar radius. The mean circular arc radius of the distal volar surface was 2.6 cm (+/-1 cm, 1-6 cm) on the radial side and 2.3 cm (+/-1 cm, 1-6 cm) on the ulnar side. A significant difference (P<.01) was noted in the radii of curvature of the distal radius in 55% of the study population. In 37% of these cases, the circular arc radius flattens toward the ulnar side. In 63%, it flattens toward the radial side. This characteristic may lead to a false rotation position of the distal fracture fragment following volar plate osteosynthesis. In addition, suboptimal or incorrect plate position may result due to the discrepancy between the plate radius of curvature and the radius of curvature of either the radial or ulnar volar radius.

Anatomy of the greater femoral trochanter: clinical importance for intramedullary femoral nailing: Anatomic study of 100 cadaver specimens

Background Fossa piriformis is considered the correct point of entry for a straight femoral nail. A trochanteric overhang may make the access to fossa piriformis difficult. We investigated the anatomy of the trochanteric region, paying special attention to the entry point for antegrade intramedullary femoral nailing. Methods and results We studied 100 cadaver specimens. In 63 specimens a shape with a free entry point was found, whereas in 37 cases the entry point was either half or fully covered. In 9 specimens the entry points could not be exactly located from a cranial aspect. Interpretation The anatomic variations of the trochanteric sometimes make it difficult to identify the correct entry point for an intramedullary nail.

Frequency of instrument breakage during orthopaedic procedures and its effects on patients.

BACKGROUND While breakage of an orthopaedic instrument is a relatively rare occurrence, orthopaedic surgeons need to be familiar with this complication and how to deal with it. Relatively little information about this subject has been published. METHODS Every case of instrument breakage during orthopaedic procedures performed in two hospitals during a two-year period was documented prospectively. All patients were followed for a postoperative period ranging from twelve to thirty-six months, during which radiographs in two planes were made to assess changes in, or migration of, the broken object. RESULTS During the observation period, 11,856 surgical procedures were performed in the two hospitals. The overall rate of instrument breakage was 0.35%. The broken piece was removed in five cases, and the broken instrument was left in situ in thirty-seven cases. During the follow-up period, none of the patients had any symptoms. CONCLUSIONS In most cases, breakage of an orthopaedic instrument is not a problem. Any instance of instrument breakage should be fully documented in the surgical report.

The risk of iatrogenic injury to the deep peroneal nerve in minimally invasive osteosynthesis of the tibia with the less invasive stabilisation system A CADAVER STUDY

Percutaneous stabilisation of tibial fractures by locking plates has become an accepted form of osteosynthesis. A potential disadvantage of this technique is the risk of damage to the neurovascular bundles in the anterior and peroneal compartments. Our aim in this anatomical study was to examine the relationship of the deep peroneal nerve to a percutaneously-inserted Less Invasive Stabilisation System tibial plate in the lower limbs of 18 cadavers. Screws were inserted through stab incisions. The neurovascular bundle was dissected to reveal its relationship to the plate and screws. In all cases, the deep peroneal nerve was in direct contact with the plate between the 11th and the 13th holes. In ten specimens the nerve crossed superficial to the plate, in six it was interposed between the plate and the bone and in the remaining two specimens it coursed at the edge of the plate. Percutaneous insertion of plates with more than ten holes is not recommended because of the risk of injury to the neurovascular structures. When longer plates are required we suggest distal exposure so that the neurovascular bundle may be displayed and protected.

Drilling, not a benign procedure: Laboratory simulation of true drilling depth

INTRODUCTION Drilling is an integral part of almost all boney operations. Various anatomical structures coursing close to the bone are at risk if the drill bit projects beyond the far cortex. Aim of this study was to evaluate and quantify the depth to which surgeons over drill beyond the far cortex. MATERIALS AND METHODS During an AO course 153 (41 females, 112 males) surgeons and physicians were invited to participate in this study. Each participant performed 3 bicortical drillings on generic artificial bone. Polystyrene plates were mounted on the far cortex of the bone to allow for exact measurement of the over penetration of the drill bit. RESULTS A total of 462 bicortical drilling manoeuvres were analysed. The average projection of the drill bit beyond the far cortex was 6.31 mm. No significant statistical correlation was noted between the specialty or the experience of the participant and depth of over drilling. CONCLUSIONS It is remarkable that the mean and the range of far cortex over-penetration was quite similar amongst surgeons of differing grades and experience. The results of this study should return to mind to pay attention when drilling particularly in anatomical sites where nerve and vessels coursing close to the far cortex.