Wedge osteotomy combined with internal fixation in the treatment of Mayo IIB olecranon fractures.

OBJECTIVE: This study aimed to biomechanically compare the maximum rotational, axial movements, and compression forces between fracture fragments before and after 1-4 mm fracture site resorption among interlocking nails, compression nails, and newly designed compressive anti-resorption (CARES) nails compressed with tube and coil spring. METHODS: We determined the maximum axial/rotational movements and interfragmentary compression loads between fragments on 10 interlocking nails, 10 compression nails, and 10 CARES nails with 30 composite femurs. Using a compression-distraction testing device, 6 N·m external and internal torques were applied, and we evaluated the maximum rotational and axial displacement between fragments after 1-4 mm fracture site resorption. RESULTS: When 6 N·m of internal-external rotation torque was applied after 2 mm fracture site resorption, the maximum rotational displacement between fragments in the CARES nail was 3 ± 0.52 mm, 101% less than the 6.03 ± 0.83 value in the compression nail and 100% less than the 6 ± 1 mm value measured in the interlocking nail (P=.000). The compression between fragments was 298 ± 72 N in the CARES nail after 1 mm of resorption, while this value was measured as 0 in the other nails. There was a significant difference in rotational, axial stability, and interfragment compression among the different femoral nails after 1-4 mm fracture site resorption. CONCLUSION: The CARES nail having additional coil springs seems significantly biomechanically superior to compression nails and interlocking nails, providing maximum rotational, axial stability, and interfragment compression after fracture site resorption.

Biomechanical comparison of fracture site stabilities of femur nails after fracture site resorption.

Instability increases after fracture site resorption. This study aimed to compare the fracture site stabilities of different femoral nails after fracture site resorption. Thirty composite femurs were divided into three groups of 10 interlocking nails. Using axial compression-distraction machines and a custom-made torsion device, the fracture site rotational and axial stabilities after 1 mm fracture site resorption were determined. Between 6 Nm external and 6 Nm internal rotation torques, the means of the maximum fracture site rotation arc of motion were 5.94 mm for compression nails, 5.9 mm for interlocking nails and 3.5 mm for CAROT nails. Between 2300 N compression and 150 N distraction forces, the means of the fracture site axial motion were 3.15 mm for interlocking nails, 1.26 mm for compression nails and 1.26 mm for CAROT nails. CAROT nails are superior to compression and interlocking nails in fracture site rotational and axial stabilities after 1 mm fracture site resorption.

A Bilateral Traumatic Hip Obturator Dislocation.

A case of a bilateral simultaneous traumatic obturator dislocation of both hip joints in an 18-year-old young man following a traffic accident is presented. We reduced the dislocated femoral heads immediately under general anesthesia followed by passive and active exercises and early full-weight bearing mobilization. After 5 years, the result was excellent.

The functional results of tibial shaft fractures treated with intramedullary nail compressed by proximal tube.

Nailing of tibial shaft fractures is considered the gold standard surgical method by many surgeons. The aim of this retrospective study was to investigate and compare the clinical outcome of tibial shaft fractures treated with intramedullary nails compressed by proximal tube and conventional intramedullary interlocking nails. Fifty-seven patients with tibial shaft fractures, treated with intramedullary nails compressed by proximal tube (n = 32) and the conventional interlocking nails (n = 25), were reviewed. All fractures except for one were united without any additional surgical intervention in the proximal compression tube nail group, whereas in the conventional interlocking nail group, six patients needed dynamization surgery (p = 0.005) and three cases of nonunion were recorded. In the proximal compression tube nail group, faster union occurred in 20 ± 2 (16-24) weeks (mean ± SD; range) without failure of locking screws and proximal nail migration, whereas in the conventional interlocking nail group, union occurred in 22 ± 2.5 (17-27) weeks (p = 0.001) with two failures of locking screws and two proximal nail migration. The proximal compression tube nail system is safer than the conventional nailing methods for the treatment for transverse and oblique tibial shaft fractures with a less rate of nonunion, proximal locking screw failure and proximal nail migration.

A new femoral nail with single distal locking screw for maximum interfragment rotational stability.

OBJECTIVE: One of the problems for interlocking nailing of the femur is interfragment rotation motion, affecting fracture healing. The nails with single distal locking screw are advantageous for decreasing operation time and radiation exposure. We investigated which single distal screw nail is the best for interfragment rotational stability. METHODS: We used a total of 30 composite femurs, ten for each group. We determined interfragment rotational displacement of composite femurs with three types of single distal screw nails (10 interlocking nails, 10 compression nails and 10 Mehmet anti-rotation nails compressed by tube) at 6-Nm external- 6 Nm internal and 10 Nm extern- 6 Nm internal torques, which imitating respectively the level walking and descending stairs, using an axial distraction testing machine and a custom designed rotation apparatus. RESULTS: Between 10 Nm external and 6 Nm internal torques with single distal locking screw, the interfragment rotational displacement in the Mehmet nail compressed by the 8 Nm torque wrench was mean 1.14 mm and 540% less than mean 7.31 mm in interlocking nails and 400% less than 5.72 mm in compression nails compressed by the 2.5 Nm torque wrench. CONCLUSION: The single distal screw Mehmet nail is superior than other single (or even some double) distal screw nails for maximum rotational stability, with no interfragment distraction gap, no superior nail migration, decreased operation time, and less radiation exposure in axially stable transverse and short oblique femur fractures in daily activities like stair descending or level walking.

Reliability of threaded locking screws.

OBJECTIVE: A frequent problem for interlocking nailing that affects the treatment of the fracture is locking screw deformation. The aim of this study is to determine whether bending resistance is different between high, low, and unthreaded locking screws of interlocking femoral nails. METHODS: Ninety screws were used in this experimental study, with 10 screws used in each of 9 groups. Three-point bending tests were performed on 6 groups of 5 mm screws (titanium, stainless steel, crossed with unthreaded, low threaded, and high threaded) and the same 3 thread types of 5.5 mm stainless steel screws in a 30-mm inner diameter steel tube, imitating the level of the lesser trochanter. An axial compressor was used to determine the yield points for permanent deformation in the locking screws by way of 3-point bending tests. RESULTS: The mean yield point value of the 3-point bending tests of 5-mm low threaded stainless steel locking screws was 2071 N, 53% less than that of unthreaded screws (3169 N). The mean yield point value of 5-mm high threaded stainless steel locking screws was 556 N, 272% less than that of low threaded screws (2071 N). CONCLUSION: To avoid locking screw deformation, high threaded screws must not be used as locking screws. In cases of unreliable patients, 5-mm low threaded screws should not be used in the nailing of comminuted or oblique femur shaft fractures. All 5-mm unthreaded screws and 5.5-mm low threaded stainless steel screws can be used safely in full weight-bearing conditions of unreliable patients.

Biomechanical comparision of femoral intramedullary nails for interfragmentary rotational stability.

OBJECTIVES: This study aims to investigate which intramedullary nail is biomechanically better for establishing interfragmentary rotational stability. MATERIALS AND METHODS: Thirty composite femurs were utilized in this study. We analyzed interfragmentary rotational arc displacements between 10 Nm external-6 Nm internal torques and 6 Nm external-6 Nm internal torques which imitate rotation torques while walking on a flat surface and descending stairs by administering 10 interlocking nails, 10 compression nails, and 10 Mehmet anti-rotation nails with tube compression. RESULTS: Maximum interfragmentary rotation arc displacement between 10 Nm external rotation and 6 Nm internal rotation torques was mean 1.64 mm in the Mehmet nail compressed by 7 Nm torque wrench. This value was lower by 309% (6.72 mm) from interlocking nail (p=0.000), 201% (5.42 mm) from compression nail compressed by 2.5 Nm torque wrench (p=0.000), and 26% (1.92 mm) from compression nail compressed by 7 Nm torque wrench (p>0.05). CONCLUSION: In axially stable transvers and short oblique femur fractures, Mehmet nail is superior to other intramedullary nails with limited movement between locking screw and hole, more interfragmentary compression without locking screw deformation, and no proximal nail migration.

Biomechanical comparison of three-point bending resistance of titanium and stainless steel locking screws in intramedullary nails.

OBJECTIVES: This study aims to investigate whether there is any significant difference in bending resistance between titanium and stainless steel locking screws of femur nails and to review deformation of locking screws which is a common problem in interlocking nailing. MATERIALS AND METHODS: In this study, a total of 60 pieces of 5 mm major diameter titanium and stainless steel locking screws were used as six groups in three different thread depth structures (high threaded, low threaded, and unthreaded). Three-point bending tests were conducted on steel screws placed inside stainless steel tube with 30 mm inner diameter, which imitated the level of lesser trochanter. We used an axial compression testing machine in order to determine the yield points that permanent deformation occurred in the locking screws. RESULTS: For low threaded locking screws, which are the most frequently used thread type for locking screws, the mean bending yield points were 1413 N on the titanium screws and this level was below 1922 N (2.8 BW) of level walking loading on femur for 70 kg person. On low threaded stainless screws, bending resistance was 2071 N, which was above the value of 1922 N. For high threaded locking screws, the mean bending yield points were 874 N on the titanium screws and 556 N on stainless screws. CONCLUSION: In comminuted femur shaft fractures (in full load bearing conditions), using stainless steel locking screws is better instead of titanium screws to avoid locking screw deformation since low threaded stainless steel screws were 46.5% more resistant to bending deformation than titanium ones. Stainless steel or titanium high threaded locking screws may only be carefully used in non-comminuted fractures.

A new compression design that increases proximal locking screw bending resistance in femur compression nails.

The aim is to present our new method of compression, a compression tube instead of conventional compression screw and to investigate the difference of proximal locking screw bending resistance between compression screw application (6 mm wide contact) and compression tube (two contact points with 13 mm gap) application. We formed six groups each consisting of 10 proximal locking screws. On metal cylinder representing lesser trochanter level, we performed 3-point bending tests with compression screw and with compression tube. We determined the yield points of the screws in 3-point bending tests using an axial compression testing machine. We determined the yield point of 5 mm screws as 1963±53 N (mean±SD) with compression screw, and as 2929±140 N with compression tubes. We found 51% more locking screw bending resistance with compression tube than with compression screw (p=0,000). Therefore compression tubes instead of compression screw must be preferred at femur compression nails.

Co-occurrence of rheumatoid arthritis and sarcoidosis.

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterised by erosive arthritis. Sarcoidosis is a chronic disease characterised by formation of non-calcified granulomas. Our case, a 35-year-old woman, presented with metacarpophalangeal, proximal interphalangeal (PIP) joints and arthritis of both ankles, of 6-month duration. She had morning stiffness lasting 1 h, restriction of range of motion and erythaema nodosum. Laboratory tests showed elevated acute phase responses and serum ACE levels, and anti-cyclic citrullinated peptide antibody positivity. There was periarticular osteoporosis on her hand and wrist on direct X-rays and hilar lymphadenopathy on her thorax CT. The pathological result of endobronchial ultrasound biopsy showed non-calcified granuloma congruent with sarcoidosis. According to clinical, laboratory and histopathological evaluation, the patient was diagnosed with RA and sarcoidosis. Corticosteroids and methotrexate were started, and on her sixth month of follow-up, her clinical and laboratory findings and lymphadenopathies on CT had regressed. The clinical follow-up continues; the patient appears to be in clinical remission.