Herbert Maurer

The antero-inferior (transmuscular) approach for arthroscopic repair of the bankart lesion: An anatomic and clinical study

In order to find a direct approach to the antero-inferior third of the glenoid rim, an anatomic study was performed on a total of 89 shoulders (48 cadavers). To obtain defined reference points for the anterior inferior third of the glenoid cavity, it was compared with the hour markings on a clock face. The 4:30 position on the right shoulder and the 7:30 position on the left shoulder were defined as the relevant reference points. The average distance between the palpable end of the coracoid process and the 4:30 and 7:30 positions was 19 mm. The average distance to the point of intersection of the musculocutaneous nerve with the medial margin of the conjoined tendon was more than 5 cm, and was never less than 2 cm. The average distance of the axillary nerve from the 4:30 position was 2.5 cm in the horizontal plane, with a minimum of 1.5 cm. Radially, the average distance of the axillary nerve was 1.7 cm, with a minimum of 1.3 cm. The anatomic study was followed by a clinical study of 264 patients. An antero-inferior portal located maximum 2 cm distal from the palpable coracoid tip was selected for the introduction of a trocar sheath and blunt trocar, passing through the subscapularis muscle to access the antero-inferior area of the glenoid rim. As additional protection for the musculocutaneous nerve, the direction of the trocar was adjusted during introduction. Reattachment of the labrum-capsule complex was performed extra-articularly. In all cases, at least one implant was located inferior to the 4:30 or 7:30 position. No neurovascular complications arose out of the choice of portal. Out of the 264 patients, the first 100 shoulders (98 patients) were followed-up after an average time of 35 months (18 to 62 months). The recurrence rate was 9%. Excluding the first 30 shoulders (30 patients) from the development phase of the technique, the recurrence rate is only 5.7%. The rate of return to overhead sports activities was 62% and to collision sports activities 70%.

Intrapelvic complications after total hip arthroplasty failure

BACKGROUND Severe total hip arthroplasty failure with central migration of prosthetic components is uncommon. If perforation of the medial acetabular wall occurs, injuries of intrapelvic structures may result. DATA SOURCES A meta-analysis of the English literature was performed. A human pelvic cadaver was used to demonstrate the proximity of intrapelvic structures to a centrally dislocated cup. RESULTS Fifty cases of intrapelvic injury were identified. Structures involved most frequently were the external iliac artery and the bladder. The most common types of complication included fistula formation, development of a false aneurysm, and hemorrhage. The human cadaver pelvis demonstrated the proximity of intrapelvic vessels, the bladder, the ureter, the vagina, the deferent duct, the sigmoid colon, the rectum, and the sciatic nerve to an intrapelvically intruded prosthesis. CONCLUSIONS Failed total hip replacements should be considered to cause damage to pelvic viscera.

The Anatomy of the Angular Branch of the Thoracodorsal Artery

This study reports an anatomical investigation of the angular branch of the thoracodorsal artery, which can be used in reconstructive surgery to serve as a pedicle for gaining osseous material from the scapula. The study was performed on 135 samples and topography and morphometry of the vessel were investigated. It was found that this artery has five main types of origin. It courses in the fascial gliding layer between the serratus muscle, and the teres major and subscapular muscle to the inferior angle of the scapula. There it provides the bone with blood through periostal branches as part of the arterial rete on the costal and dorsal side of the scapula. The mean length of the angular branch and the thoracodorsal artery together was 148 mm, and when also adding the subscapular artery the overall length became 167 mm. It was found that the length of a pedicle consisting of the angular branch and the thoracodorsal artery is determined by the difference in origin of the vessels with minor influences of the body size. The internal diameters of unfilled fixated vessels measured 3.06 mm for the subscapular, 1.77 mm for the circumflex scapular, 1.30 mm for the thoracodorsal and 0.64 mm for the angular branch. The exact knowledge of the microanatomy in this area is necessary to be able to use the osseous free flap more selectively and have less traumatization in the donor area.

Knee pain caused by a fiducial marker in the medial femoral condyle: A clinical and anatomic study of 20 cases

After 2-pin-based ROBODOC hip arthroplasty procedures, 10 of 18 patients reported persistent severe pain at the site of pin implantation in the medial femoral condyle. In a cadaver study, we found that the infrapatellar branch of the saphenous nerve, the saphenous nerve and the anterior cutaneous branches of the femoral nerve had been injured by the pins. At least one of these nerves was injured in 11 of the 20 specimens examined. Our findings indicate that the knee-pain may be partly caused by injuries to these nerves.

Pectoralis major inverse plasty for functional reconstruction in patients with anterolateral deltoid deficiency

After establishing anatomical feasibility, functional reconstruction to replace the anterolateral part of the deltoid was performed in 20 consecutive patients with irreversible deltoid paralysis using the sternoclavicular portion of the pectoralis major muscle. The indication for reconstruction was deltoid deficiency combined with massive rotator cuff tear in 11 patients, brachial plexus palsy in seven, and an isolated axillary nerve lesion in two. All patients were followed clinically and radiologically for a mean of 70 months (24 to 125). The mean gender-adjusted Constant score increased from 28% (15% to 54%) to 51% (19% to 83%). Forward elevation improved by a mean of 37 degrees , abduction by 30 degrees and external rotation by 9 degrees . The pectoralis inverse plasty may be used as a salvage procedure in irreversible deltoid deficiency, providing subjectively satisfying results. Active forward elevation and abduction can be significantly improved.

Minimally invasive approaches and surgical procedures in the lumbar spine

SummaryThe history of minimally invasive lumbar spine surgery began in 1963 with the introduction of chemonucleolysis. Like this technique, the later development of mechanical nucleotomy and lasernucleotomy aimed primarily at reduction of the disc pressure. Miniature optical systems offered the opportunity for more specific decompression by discoscopy or, more recently, by transforaminal epiduroscopy. Initially, nucleotomy was the only feasible minimally invasive procedure. In recent years, however, minimally invasive spinal fusion became possible due to the development of new devices (Cages) and advanced transperitoneal (laparoscopic) and retroperitoneal approaches.ZusammenfassungDie minimal-invasiven Operationen an der lumbalen Wirbelsäule begannen 1963 mit Einführung der Chemonukleolyse. Wie diese hatte auch die später entwickelte perkutane mechanische Nukleotomie und die Lasernukleotomie zunächst nur die intradiskale Drucksenkung zum Ziel. Kleine Optiken machten eine gezieltere Dekompression mittels Diskoskopie oder zuletzt via transforaminalem Zugang mittels Epiduroskopie möglich. Während zunächst nahezu ausschließlich bandscheibenbedingte Syndrome behandelt werden konnten, ist in den letzten Jahren auch die Behandlung degenerativer Veränderungen und von Instabilitäten möglich geworden. Die Entwicklung neuer Implantate (Cages) und neuer, minimal-invasiver transperitonealer (laparoskopisch) und retroperitonealer Zugänge hat hierzu beigetragen.

Anatomic consideration for lumbar percutaneous interbody fusion.

The anatomy of the intervertebral foramina L1–S1 was studied by the dissection of 106 foramina levels in 13 human anatomic spine specimens. Twenty foramina were examined in each level from L1 to L5 and 26 foramina from L5 to S1. It appears a safe working canal diameter is 8 mm for L1–L4 and 7 mm for L4–S1.