Tibia Research Papers - Academia.edu (original) (raw)

The effects of Spinal Cord Injury (SCI) on bone in paralyzed areas are well documented but there are few data for the importance of the level of injury in the decrease of mechanical strength in paralyzed legs. The aim of the present study... more

The effects of Spinal Cord Injury (SCI) on bone in paralyzed areas are well documented but there are few data for the importance of the level of injury in the decrease of mechanical strength in paralyzed legs. The aim of the present study was to describe bone loss of the separate compartments of trabecular and cortical bone in spinal cord injured men and to compare possible changes in mechanical properties of tibia with the neurological level of injury. Fifty men were included in this study: 39 had complete SCI in chronic stage. As chronic stage, we considered paraplegia >1.5 years (yrs). Men were separated as follows: Group A (18 men, high paraplegia: Thoracic (T)4-T7 level, mean age: 33 yrs, duration of paralysis: 5.9 yrs) and group B (21 men, low paraplegia: T8-T12 level, mean age: 39 yrs, duration of paralysis: 5.6 yrs) in comparison with 11 healthy men as a control group (C) of similar age, height, and weight. None of the subjects was given bone acting drugs. The neurologica...

The pharmacokinetics and bone concentrations of oritavancin were investigated after a single intravenous dose was administered to rabbits. The pharmacokinetic profile of oritavancin in rabbits showed that it is rapidly distributed to bone... more

The pharmacokinetics and bone concentrations of oritavancin were investigated after a single intravenous dose was administered to rabbits. The pharmacokinetic profile of oritavancin in rabbits showed that it is rapidly distributed to bone tissues, with concentrations remaining stable for up to 168 h, the last measured time point. Based on these findings, further evaluation of oritavancin for the treatment of infections in bone tissues is warranted.

This study investigated the concept of using plates to attach endoprostheses to bone after segmental resection for bone tumours in an animal model. Titanium alloy plates integrated with the prosthesis and coated with hydroxyapatite were... more

This study investigated the concept of using plates to attach endoprostheses to bone after segmental resection for bone tumours in an animal model. Titanium alloy plates integrated with the prosthesis and coated with hydroxyapatite were attached to bone by screws. This type of uncemented fixation relied on the induction of periosteal bone formation into and around the plates to secure the implant to bone. Tow, three, and six-slotted plate designs were investigated. On retrieval, each plate was securely fixed by new bone. Bone apposition on the external surface of the plates occurred through a combination of periosteal bone production, invasion of bone through slots in the plate, and bone growth over the ends of the plates. Most plates became incorporated into a remodelled cortex. Higher bone turnover rates (μm day−1) were seen in bone in the slots of the plate compared with normal cortical bone turnover (p < 0.05). Significantly higher rates of turnover were measured beneath slotted parts of the plates compared with regions below the unslotted parts (p < 0.05). The cross-sectional area of bone surrounding the six-plate implant design was significantly higher than that of the three-plate (p < 0.05) and two-plate (p < 0.05) designs. In addition, significantly more bone formed adjacent to the six-plated implant design compared with that in the contralateral limb (p = 0.002). However, no significant difference was found when the total cortical area around the three-plated design was compared with that of the contralateral limb (p = 0.63). In contrast, significantly less bone was measured adjacent to the two-plate design than in the untreated limb (p = 0.001). Image analysis also demonstrated increased cortical porosity adjacent to the six-plate design compared with the three-plate (p = 0.004) and two-plate (p < 0.05) designs. Finite element analysis demonstrated that the six and three-plate designs increased the second moment of area compared with that in the left tibia (p = 0.003 and 0.066, respectively). However, the attachment of the more flexible two-plate design did not significantly increase the second moment of area compared with that in the contralateral limb (p = 0.235). It was concluded that due to both mechanical and biological effects, the hydroxyapatite-coated plate designs generated new bone that enhanced fixation and encouraged plate integration into the load-bearing structure of the cortex. This method of fixation may be an alternative to the use of intramedullary cemented stems in patients requiring bone tumour implants and may be the only way to preserve the joint in difficult cases where only short segments of bone remain.

Skin defects on the distal extremity (n = 7) or face (n = 1) of eight dogs were repaired using a medial saphenous fasciocutaneous or myocutaneous flap. The cause of the wounds were ablative oncological surgery (n = 4), trauma (n = 3), or... more

Skin defects on the distal extremity (n = 7) or face (n = 1) of eight dogs were repaired using a medial saphenous fasciocutaneous or myocutaneous flap. The cause of the wounds were ablative oncological surgery (n = 4), trauma (n = 3), or radiation burn (n = 1). The flap was removed from the medial femorotibial region, and transferred to the wound bed. The vascular supply to the flap was reestablished via microvascular anastomosis of the medial saphenous vessels of the flap to recipient vessels isolated adjacent to the wound. Three flaps incorporated the distal half of the caudal head of the sartorius muscle to form a myocutaneous free flap. All flaps survived completely. The medial saphenous fasciocutaneous and myocutaneous free flaps were found to be reliable and cosmetically acceptable for repair of skin defects in dogs.

Impingement by the distal fascicle of the anterior inferior tibiofibular ligament (AITFL) is a relatively new entity among the known causes of anterolateral impingement syndromes of the ankle. This study investigated the anatomy of the... more

Impingement by the distal fascicle of the anterior inferior tibiofibular ligament (AITFL) is a relatively new entity among the known causes of anterolateral impingement syndromes of the ankle. This study investigated the anatomy of the anterior inferior tibiofibular ligament and its possible role in talar impingement in 47 ankles of 27 cadavers. The length, width, insertion point to the fibula and the interactions with talus were noted, as was the relationship of the fascicle and talus during different ankle movements before and after incision of the lateral ligaments. A distal fascicle of the AITFL was found in 39 of the 47 ankles (83%) and appeared as a single-complete ligament in the remaining 8 ankles (17%). The fascicle averaged 16.1±2.94 mm in length (range 10–21) and 4.2±1.00 mm in width (range, 3–7). The insertion point of the fascicle on the fibula averaged 10.3±2.27 mm (5–13) distal to the joint level. Contact between the ligament and the lateral dome of the talus was observed in 42 specimens (89.3%). Bending of the fascicle was observed in 8 of these 42 ankles with forced dorsiflexion. These 8 specimens were significantly wider and longer than the specimens without bending of the fascicle. Incision of the anterior talofibular ligament led to bending in dorsiflexion in additional 11 ankles. The total 19 fascicles with bending after incision of the anterior talofibular ligament were significantly longer and inserted more distally than the remaining 20 fascisles without bending. Manual traction simulating distraction during arthroscopic procedures relieved the contact. These findings show that the presence of the distal fascicle of the AITFL and its contact with the talus is a normal finding. However, it may become pathological due to anatomical variations and/or instability of the ankle resulting from torn lateral ligaments. When observed during an ankle arthroscopy, the surgeon should look for the criteria described in the present study to decide whether it is pathological and needs to be resected.

Squamous cell carcinoma (SCC) is a rare but well-documented complication of chronic osteomyelitis. Between February 1991 and March 1999, 13 cases (12 men and one woman) of SCC arising in chronic osteomyelitis were diagnosed and treated in... more

Squamous cell carcinoma (SCC) is a rare but well-documented complication of chronic osteomyelitis. Between February 1991 and March 1999, 13 cases (12 men and one woman) of SCC arising in chronic osteomyelitis were diagnosed and treated in our clinic. Mean age was 56.5 (38–70) years. Twelve patients underwent amputation and one underwent limb salvage. Average follow-up was 56 (24–121) months. Among the 13 patients two died of the disease. Treatment of choice for these tumours has been amputation. Carcinome cellulaire squameux est une complication d'ostéomyélite, peu fréquente, mais bien connue. Entre le février 91–mars 99, dans notre clinique, nous ont constate 13 malades (12 hommes et 1 femme) a qui nous ont vu la maladie développe a la base d'ostéomyélite chronique. L'age moyen était 56.5. (38–70) 12 malades ont subi une amputation et dans l'autre l'extrémité a été gardée. La surveillance a duré à peu près 56 (24–121) mois. Parmi ces 13 malades seulement deux sont morts. Pour ces tumeurs on peut dire que l'amputation est la méthode la plus efficace.

Bones adapt to prevalent loading, which comprises mainly forces caused by muscle contractions. Therefore, we hypothesized that similar associations would be observed between neuromuscular performance and rigidity of bones located in the... more

Bones adapt to prevalent loading, which comprises mainly forces caused by muscle contractions. Therefore, we hypothesized that similar associations would be observed between neuromuscular performance and rigidity of bones located in the same body segment. These associations were assessed among 221 premenopausal women representing athletes in high-impact, odd-impact, high-magnitude, repetitive low-impact, and repetitive nonimpact sports and physically active referents aged 17–40 years. The whole group mean age and body mass were 23 (5) and 63 (9) kg, respectively. Bone cross sections at the tibial and fibular mid-diaphysis were assessed with peripheral quantitative computed tomography (pQCT). Density-weighted polar section modulus (SSI) and minimal and maximal cross-sectional moments of inertia (Imin, Imax) were analyzed. Bone morphology was described as the Imax/Imin ratio. Neuromuscular performance was assessed by maximal power during countermovement jump (CMJ). Tibial SSI was 31% higher in the high-impact, 19% in the odd-impact, and 30% in the repetitive low-impact groups compared with the reference group (P < 0.005). Only the high-impact group differed from the referents in fibular SSI (17%, P < 0.005). Tibial morphology differed between groups (P = 0.001), but fibular morphology did not (P = 0.247). The bone-by-group interaction was highly significant (P < 0.001). After controlling for height, weight, and age, the CMJ peak power correlated moderately with tibial SSI (r = 0.31, P < 0.001) but not with fibular SSI (r = 0.069, P = 0.313). In conclusion, observed differences in the association between neuromuscular performance and tibial and fibular traits suggest that the tibia and fibula experience different loading environments despite their anatomical vicinity.

Revision surgery for failed unicompartmental knee arthroplasty (UKA) with bone loss is challenging. Several options are available including cement augmentation, metal augmentation, and bone grafting. The aim of the present study was to... more

Revision surgery for failed unicompartmental knee arthroplasty (UKA) with bone loss is challenging. Several options are available including cement augmentation, metal augmentation, and bone grafting. The aim of the present study was to describe a surgical technique for lateral tibial plateau autografting and report mid-term outcomes. Eleven consecutive patients (median age 69.5 years) affected by posteromedial tibial plateau collapse after medial UKA were enrolled in the present study. The delay between UKA and revision surgery was 21 months (range 15-36 months). All patients were revised with a cemented posterior-stabilized implant, with a tibial stem. Medial tibial plateau bone loss was treated with an autologous lateral tibial plateau bone graft secured with two absorbable screws. All patients were evaluated with the Oxford Knee Score (OKS), visual analogue scale for pain (VAS), and complete radiographic evaluation. At a median follow-up of 60 months (range 36-84 months), the OKS...

The use of, and interest in, total knee replacements (TKR) has been growing over the last few decades. Loosening and migration of tibial components have been identified as one of the primary causes of failure in the proximal tibia.... more

The use of, and interest in, total knee replacements (TKR) has been growing over the last few
decades. Loosening and migration of tibial components have been identified as one of the
primary causes of failure in the proximal tibia. Clinical studies show the use of metal
implants as one of the primary methods for the treatment of knee joints and associated bone
defects. Alignment and fixation techniques play an important role in achieving high success
rates. Defective bone stock requires the use of augments to stabilise the tibial plate. In these
cases, current clinical practice is to use an extended implant stem to ensure stability. The
problem with this is that it reduces the potential for future knee revision
In this research Finite Element Analysis (FEA) has been used to undertake virtual in-vivo
assessment of various configurations of augmented and non-augmented TKR that can be used
for the treatment of tibial defects. These configurations are based on a standard tibial insert,
namely a fixed bearing revision tibial tray. This has provided insight and information that can
be used to improve surgical decision making when dealing with defective bone stock.
The 3D FE models of a non-defect TKR with a fixed bearing tibial insert showed a stable
construct with stresses lying within an allowable threshold. The use of a stem extension
generally showed a reduction in stress levels in the cancellous bone contributing to an
increase in stress shielding and thus it is recommended that these are not used unless there is
some other overriding clinical requirement.
Further, the analysis demonstrated that, contrary to some clinical opinion, wedge
augmentation (rather than block augmentation) may provide a better approach to treat the
defect. This was largely due to improved cement stress distribution caused by a mechanism
termed “reverse-shear”.
The use of a cement augment was found to provide a more favourable stress distribution in
the cancellous bone. However, metal augments have been recommended as the cement
augment was shown to operate too close to its fatigue endurance limits.