Reimers migration percentage (MP) is a key measure to inform decision-making around the management of hip displacement in cerebral palsy (CP). The aim of this study is to assess validity and inter- and intra-rater reliability of a novel method of measuring MP using a smart phone app (HipScreen (HS) app). A total of 20 pelvis radiographs (40 hips) were used to measure MP by using the HS app. Measurements were performed by five different members of the multidisciplinary team, with varying levels of expertise in MP measurement. The same measurements were repeated two weeks later. A senior orthopaedic surgeon measured the MP on picture archiving and communication system (PACS) as the gold standard and repeated the measurements using HS app. Pearson’s correlation coefficient (r) was used to compare PACS measurements and all HS app measurements and assess validity. Intraclass correlation coefficient (ICC) was used to assess intra- and inter-rater reliability.Aims
Methods
The autologous osteochondral grafting represents a treatment option for osteochondral lesions of the weight bearing articular surfaces of femoral condyles and talus. The aim of our study was to evaluate the MRI findings and to determine the correlation between the radiological and the functional outcome in the early follow up. We performed a retrospective study and followed up 33 patients 1 to 4 years after osteochondral auto-grafting. The grafts were harvested from the anterolateral region on the lateral femoral condyle of the ipsilateral knee using an insider rinsing diamond bone-cutting instrument (DBCS). The grafts were implanted using press fit technique and mosaic plasty. Sixteen (48%) women and 17 men were included in our follow up with an average age of 38.4 years (age range-16 to 58 yrs). The Lysholm and Foot and Ankle Osteoarthritis Scores were used for the assessment of the functional outcome. MRI scans were performed by all patients. While the MRI results illustrated graft incorporation, the cartilage contour interruption, irregularity of the subchondral lamina, inhomogeneity and subchondral oedema are typical findings between host and graft tissues. The clinical outcome demonstrated pain relief and improved function. There was no statistically significant correlation between radiological and functional outcome (p>0.05). The MRI is a well-recognised non-invasive diagnostic tool to assess the integration of osteochondral grafts and to evaluate the articular surface but it has a reduced clinical significance on the early post operative stages. The long-term prognostic value of the unsatisfying MRI results is unknown.
The radiological and biomechanical assessment using cement augmented cannulated pedicle screw (Biomet®, Omega 21®) and the correlation of the cement volume to the pullout strength needed for each screw Cadaveric vertebrae of different lumbar levels were used. Through cannulated pedicle screw a definite volume of cement was applicated. The bone volume occupied by cement was assessed by means of segmentation after Computer Tomography. Biomechanical Pullout tests and statistical correlation analysis were then performed The maximum pullout strength was 1361 N and the minimum pullout strength was 172 N (SD 331 N). The maximum cement volume was 5,29 cm3 and the minimum 1,02 cm3 (SD 1,159). The maximum cement diameter was 26,6 cm and the minimum cement diameter was 20,7 cm (SD 1,744). There is statistically significant correlation between the pullout strength and the injected cement volume (p<
0,05). The cannulated pedicle screw was used for a better fixation in the vertebral body. The cement augmentation with this technique is easier and seems to be safer than cement augmentation of non cannulated screws. Pullout strength of the cannulated screws correlates positively with the cement volume. It is though not influenced either by the total vertebral volume or by the ratio cement volume to vertebral volume or by the maximum diameter of the cement drough
The influence of the intravertebral length of vertebral screws on their pull out strength. 64 Cadaveric vertebrae of different lumbar levels were used. By means of Computer Tomography the length of the screw in the bone was assessed. The ratio screw length in bone to the longest possible screw in bone was built. Biomechanical Pullout tests and statistical correlation analysis were then performed The maximum pullout strength was 1602 N and the minimum pullout strength was 96,4 N (SD 356,9 N). The maximum ratio of the inserted screw was 95,9% and the minimum was 58,8% (SD 0,7%). There is no statistically significant correlation between the ratio of the inserted screw and the pullout strength needed. Moreover, there is a statistically significant correlation between bone mass density and pullout strength (p<
0,05). The fixation of pedicle screws is better in a non osteoporotic vertebral body. Pullout strength and bone mass density correlate significantly whereas there is no correlation between the insertion length of the screw and the pullout strength under the condition that the insertion ratio is greater than 58,8 %. Factors such as insertion angle of the screw need to be evaluated, and new techniques for pedicle screw fixation in osteoporotic vertebrae need to be developed
In a study on ten fresh human cadavers we examined the change in the height of the intervertebral disc space, the angle of lordosis and the geometry of the facet joints after insertion of intervertebral total disc replacements. SB III Charité prostheses were inserted at L3-4, L4-5, and L5-S1. The changes studied were measured using computer navigation sofware applied to CT scans before and after instrumentation. After disc replacement the mean lumbar disc height was doubled (p <
0.001). The mean angle of lordosis and the facet joint space increased by a statistically significant extent (p <
0.005 and p = 0.006, respectively). By contrast, the mean facet joint overlap was significantly reduced (p <
0.001). Our study indicates that the increase in the intervertebral disc height after disc replacement changes the geometry at the facet joints. This may have clinical relevance.
The osteochondral defect in the knee and ankle joint is a difficult and common problem in young population. The bone-cartilage autologous grafting represents a recently introduced treatment option for osteochondral lesions of the weight bearing articular surfaces of femoral condyles and talus. The aim of our study was to evaluate the MRI findings, and in particular to find out about the fate and the time needed for the graft incorporation, to assess the continuity, homogeneity and smoothness of the cartilage layer of the transplant compare to the remaining cartilage, to estimate the viability of the graft and to determine the correlation between the MRI findings and the functional outcome. We performed a prospective study and followed up 33 patients, who underwent osteochondral autografting for defects in both medial and lateral femoral condyles as well as in the talus. The grafts were harvested from the anterolateral region of the ipsilateral knee using an insider rinsing diamond bone-cutting instrument (DBCS). The grafts were implanted using press fit technique. 16(48%) women and 17 men were included in our followup with an average age of 38.4 years (age range-16to58 yrs). There were 20(60%) osteochondral defects in the femoral condyles and 13 in the talus. 13(40%) patients gave a history of trauma. All the patients were followed up with MRI scans between 1 to 4 years postoperatively. The MRI study illustrated a cartilage contour interruption by 16(48%) patients and 19(58%) had uneven joint surface. 9(27%) of the patients were shown to have homogeneity between the graft and the surrounding bone and cartilage tissues. A subchondral oedema was observed in 2(6%) of the cases. Only 1 patient had a subchondral bone-oedema in the graft-donor site. All the autologous grafts were incorporated by 4 years as proven by MRI scans The MRI evaluation revealed regular incorporation of the osseous part of the graft in the subchondral bone. On the contrary, cartilage layer integration was less common. The MRI findings did not show any correlation to the clinical outcome. Hangody (2003) reports all grafts to incorporate into the recipient bed and most articular surfaces to have congruency and similar appearance to the surrounding articular cartilage and bone in 6 years. Despite using very accurate harvested autologous osteochondral cylinders, which fit exactly the defects, match precisely the corresponding chondral and osseous layers and cause no immune reactions, it was shown in this short term MRI followup that the height and the shape of the original articular surface cannot be fully restored. However the relief of symptoms and improved functional outcome are promising findings and define bone cartilage autografting as a currently efficient treatment of osteochondral lesions of knee and talus.
