Mehmet Türker

Rotational deformity affects radiographic measurements in distal radius malunion

Malunited distal radius fractures are 3D deformities. The preoperative evaluation of the deformity and surgical planning are usually depended on plain radiographic measurements for corrective osteotomies. In most of the cases, the rotational deformity is disregarded in preoperative planning. We aimed to clarify the effect of rotational deformity on radial inclination and dorsal or volar tilt measurements, which are commonly used as radiologic parameters. This study was performed on standard left radius saw bone models. The malunion models were prepared according to AO distal radius fracture classification system in four main and seventeen subgroups. The differences between the mean radial inclination, volar or dorsal tilt measurements performed on plain radiographies and gold standard values were statistically analyzed. Results showed that rotational deformity causes faulty measurements of radial inclination and dorsal tilt on plain radiographies which may be a contributing factor for unsatisfactory clinical results of corrective osteotomy. We suggest 3D preoperative evaluation of the deformity if possible.

Over-the-top knot placement technique enhances tensile stability of tendon repairs.

Background: Currently a major concern for the surgical treatment of Achilles tendon rupture repairs is the creation of stable enough fixation to allow early range of motion. It was documented that the weakest point in a suture loop is the knot. Thus, we hypothesized that moving the knot away from the repair junction (over-the-top Krackow technique) would increase the strength of the repair. Materials and Methods: Transected bovine tendons were repaired by the traditional Krackow and over-the-top Krackow techniques using four suture materials (Fiberwire Nos. 5 and 2, Ethibond Nos. 5 and 2). Tendons were cyclically tested at incremental loads beginning from 50 N until 5-mm gap formation. Then all tendons were loaded to failure. The number of cycles to 5-mm gapping, ultimate failure loads and knot slip were compared using t-test and Mann-Whitney tests (with Tukey corrections for multiple comparisons). Results: Mean number of cycles to 5-mm gapping did not reveal significant differences (p = 0.113) between repair groups. Mean failure load of tendons repaired by over-the-top Krackow technique were significantly higher (p < 0.0001) for all four paired groups than tendons repaired by traditional Krackow technique. Ethibond No. 5, No. 2, and Fiberwire No. 2 suture repairs with over-the-top configuration did not reveal any knot slip. Conclusion: Over-the-top Krackow technique increases the ultimate failure load of repaired tendons. But 5-mm gapping resistivity was not enhanced either by the technique or the suture material. Clinical Relevance: The knot itself is a stress-riser in the suture loop so we suggest that freeing it from tension by our modificiation may achieve more durable repairs.

Effect of Partial, Distal Epicondylectomy on Reduction of Ulnar Nerve Strain: A Cadaver Study

PURPOSE To compare the decrease in ulnar nerve strains using a modification of medial epicondylectomy by removing the distal half of the medial epicondyle with in situ decompression and partial medial epicondylectomy. METHODS Using 20 elbows of 10 fresh human cadavers, we measured the strain on the ulnar nerve using a microstrain gauge before and after in situ decompression. Then, we repeated the measurements after partial medial epicondylectomy on left elbows, and after distal medial epicondylectomy on right elbows. We compared the mean strain values with 2-way analysis of variance. RESULTS The decrease in mean ulnar nerve strain with in situ decompression from 5.4% to 5.2% on the right side and 5.4% to 5.0% on the left was not statistically significant. The decrease to 2.9% on the left elbows after partial and to 1.9% on the right elbows after distal medial epicondylectomy was statistically significant. In addition, the remaining ulnar nerve strain after distal medial epicondylectomy was significantly less compared with that after partial medial epicondylectomy. We observed nerve subluxation only with partial medial epicondylectomy. CONCLUSIONS In situ decompression alone does not change ulnar nerve strains. The significant change in ulnar nerve strain with partial or distal medial epicondylectomy underlines the role of medial epicondyle on stretching of the ulnar nerve. Excision of the distal half of the medial epicondyle sets the contact point of the nerve with the bone proximally and decreases the strain on ulnar nerve more effectively than partial epicondylectomy. However, its efficacy and complications need to be studied clinically. CLINICAL RELEVANCE The results of the present cadaveric study suggest that excision of the distal half of the medial epicondyle in cubital tunnel syndrome may decrease ulnar nerve strain effectively. The clinical effect of decrease in nerve strain and the indications for the procedure need to be investigated.

Migration of broken K-wires into the achilles tendon from a ostheosynthesed medial malleolar fracture

Kirschner (K-) wires are often used for osteosynthesis of many types of fractures. Dislocation and migration through the tissues, especially when used for shoulder girdle fractures, have been reported previously. K-wire migration after surgery of pelvis and knee was reported before. To the authors’ knowledge, broken and migrated K-wires after ankle fractures were not reported before. Here, we report a case with broken and migrated K-wires after open reduction and internal fixation of a medial malleolar fracture.

Coronoid fractures and elbow instability, general review and clinical presentation

Elbow joint has three articulations: (1) ulnatrochlear, (2) radiocapitellar, and (3) radioulnar. The olecranon and coronoid fossa of distal humerus separate medial and lateral columns of the distal humerus. Medial column ends with spool-shaped trochlea, and lateral column ends with spherical capitellum. The irregularity of elbow joint in anatomic means is not an impediment for the joint to be congruent. Congruity of the ulna humeral articulation is the mainstay of the osseous stability and mobility in flexion and extension plane. Fracture dislocation of the elbow is a well-defined injury, but it is difficult to achieve satisfactory good results due to some pitfalls. Coronoid process, radial head and neck or both can be fractured. Treatment decision of uncomplicated elbow fractures depends on the stability after reduction. Understanding the anatomy and the biomechanics of elbow is crucial to diagnose and treat elbow instability. Treatment of fracture dislocation of the elbow is a challenge for the orthopedic surgeon. Here, we emphasized the anatomic and biomechanical knowledge about importance of the recognition, identification, and treatment of coronoid process in restoring the sufficient stability of the elbow to allow early mobilization with an excellent functional outcome.