M.Tech. (Chiropractic) / This study was conducted in order to determine if Chiropractic Spinal Manipulative Therapy (SMT) to the lumbar spine and Sacroiliac joints can accelerate the recovery process of the Hamstring and Quadriceps femoris muscle and thus enabling the athlete to sustain endurance levels for a longer period of time. Participants used were recruited from the cycling community by means of word of mouth. Thirty participants that matched the inclusion criteria were included in the study. The participants were then randomly divided into two groups, a Test Group and a Control Group, of fifteen participants each. Motion and static palpation was used to detect spinal restrictions. The Test Group received Chiropractic SMT to the restricted lumbar vertebral segments and the Sacroiliac joints after the first test was completed. The participants then underwent a 30 minute recovery period after which they were re-tested. The Control Group received no treatment after the first test, but still had a 30 minute recovery period after which they were re-tested. Objective measurements were taken by making use of Cybex Isokinetic Dynamometer. The objective measurement indicated that there was an increase in muscle endurance of the Quadriceps femoris and Hamstring muscle groups for both the test and the Control Group. When the increase in Hamstring and Quadriceps femoris muscle endurance was compared between the Test and Control Group, it was the Control Group that showed a more significant increase in Quadriceps femoris muscle endurance which was greater than the increase of the Quadriceps femoris muscle endurance in the Test Group. The Control Group also showed a greater increase mean endurance of the Quadriceps femoris and Hamstring muscle. In conclusion to the study, muscle endurance in cyclists can be increased by rest alone and does not require Chiropractic SMT to restricted spinal segments.

Dr. C. Yelverton

This unblinded, non-randomised pilot study was conducted in order to determine if diversified chiropractic manipulation and/or sacro occipital technic adjustments of the sacroiliac (SI) joint could increase the short-term strength of the gastrocnemius muscle. Ninety asymptomatic male patients between the ages of 20 and 30 years participated in the investigation. These patients were recruited by the use of posters that were placed in strategic areas around the Technikon Witwatersrand campus. The patients were randomly placed into one of three groups of thirty. Group FA (force adjustment) received force, side-lying, diversified sacroiliac adjustments to the sacroiliac joint. Group NA (non-force adjustment) received non-force sacro occipital technic (SOT) adjustments to the same area by means of SOT blocking technique. The third group. Group C (control) received detuned ultrasound over the SI joint. Each patient received only one treatment. The inclusion criteria required that the patient had to be male, fall inside the above age range, and presented with asymptomatic sacroiliac joint dysfunction. This was determined either by diversified chiropractic motion palpation or SOT category analysis. Only category one patients were used in this study. The objective data was collected using an isometric dynamometer. The gastrocnemius muscle strength was measured with the dynamometer before and after the treatment. The objective results indicated that there was a statistically significant increase in gastrocnemius muscle strength in both of the experimental groups. In conclusion, it has been shown that both force and non-force adjustments positively effect active muscle strength. In this case it was shown that these types of adjustments to the SI joint caused an increase in active gastrocnemius muscle strength. It is suspected that the inhibition of the motor neuron, via the capsular stretch reflex, plays a major role in the effect seen in this study. This gives further information about the underlying mechanisms of the chiropractic adjustments and may support the role of non-force techniques in treating patients. / Dr. Chris Yelverton Dr. Malany Moodley

Over the years, the lending procedures of microcredit has evolved. The original joint liability group lending with simultaneous financing (loans released at once) has been replaced by sequential financing (loans released one by one). Moreover, recent studies suggest individual liability lending in groups to be the optimal choice. While numerous theoretical studies provide thorough models of each of these approaches, none presents a comparative analysis. In this study, we model these three schemes using the framework by Van Tassel (1999) and compare them. Further, we add exogenous peer monitoring costs and within-group heterogeneity of loan sizes to our models. Our findings prove that, in the presence of information asymmetry, group lending with joint liability dominates individual liability lending in groups. Furthermore, the interest rate of the sequential model is more sensitive to changes of monitoring costs or opportunity costs of capital than in the sequential model. On the contrary, sequential approach allows for higher degree of within-group heterogeneity of loan sizes. It is ambiguous which model achieves higher profit and lower interest rate. Our results confirm that the choice of optimal financing approach is determined by the characteristics of borrowers. JEL Classificiation G2 Keywords...

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The hip joint center (HJC) is needed for calculation of hip kinematics in various applications. In the functional method, the center is determined by moving femur with respect to acetabulum. A popular way for measuring this movement is through an optical motion capture system. This method is fast and economical for most applications where we require an instant HJC even though the reconstruction error in bone position calculation exists due to skin artifact. This error is caused by movement of markers placed on skin rather than on actual bone. Here we introduce ultrasound imaging as an additional modality to measure the change in soft tissue thickness above bone while hip is flexed. We use this information on the tissue thickness change to recalculate position of markers placed on skin to match the movement of bone. A good advantage of using ultrasound machine is its non-invasiveness. We calculated HJC using a symmetric center of rotation estimation (SCoRE) algorithm, which uses the concept of coordinate transformation on 3D marker position data. The algorithm gives the 3D position of two centers, one for each hip bone. The distance between these two centers (SCoRE residual) gives us a hint on the accuracy of the HJC calculation and has been proved to be proportional to the error with respect to actual center in previous studies. These two centers should ideally coincide as they collectively form a spherical joint. Our new algorithm for HJC calculation with tissue thickness compensation, measured using ultrasound imaging shows the error has been reduced from 9.13 mm to 4.87 mm

M.Tech. (Chiropractic) / Purpose: A kinematic chain consists of a succession of joints linking several fixed components (Levangie and Norkin, 2005). Any tension or restriction within a component of this chain increases the load placed on the remaining components (Commorford and Mottram, 2001). Pathomechanics of the hip may have an effect on the areas of pressure exerted by the plantar surface of the foot during gait through the kinematic chain (Levangie and Norkin, 2005). Chiropractic manipulative therapy restores the correct biomechanical function to a joint (Gatterman, 2005). No previous research to determine the effect of hip manipulation on lower limb biomechanics and gait patterns has been identified. The purpose of this study was to determine the effect of chiropractic manipulative therapy of the hip on gait patterns, particularly the degrees of foot rotation and the pathway of the centre of pressure of the foot. Method: Sixty participants matching the inclusion and exclusion criteria for this study were recruited. The procedure, risks and benefits were explained to each of them and they were required to sign an information and consent form. The participants then underwent a full case history accompanied by a physical and hip regional examination, including motion palpation of the hip. This ensured that none of the participants matched the exclusion criteria consisting of serious gait abnormalities, contraindications to manipulation and the receipt of simultaneous forms of treatment. Individual gait analysis by the Zebris FDM-System was performed for each participant before they received a hip manipulation. A second gait analysis was then conducted to determine a change. Procedure: Each participant was required to walk barefoot over the Zebris platform for approximately 2 minutes while 3 – 5 gait cycles were recorded for gait analysis. The participant then received manipulative therapy of the restricted hip. A second gait analysis was performed just as the first. The Zebris software calculated the average results from before and after the hip manipulation and displayed the changes of foot rotation and the parameters of the pathway of the centre of pressure in a report for each participant. The focus of this study was the manipulated hip. Changes of the non-manipulated hip were mentioned only where applicable. The Zebris FDM-System allows for accurate gait analysis due to its “capacitive force sensors,” each of which possesses its own calibration curve (Zebris Medical GmbH, 2006). Results: Statistically significant changes were found for certain gait parameters representing the pathway of the centre of pressure. These included anterior/posterior variability, lateral symmetry and lateral symmetry variability. Conclusion: This study demonstrates that chiropractic manipulative therapy of the hip has an effect on certain centre of pressure parameters and chiropractors, therefore, should be consulted for the treatment of gait abnormalities. The study trial involved only a single treatment per participant. Further studies should be conducted to determine whether multiple treatments and manipulation of other kinematic chain components have an effect.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, and Woods Hole Oceanographic Institute, 1990. / Includes bibliographical references (p. 339-360). / by Hagen Schempf. / Ph.D.

Studies have shown that the alignment of the knee in the coronal plane has a significant effect on the joint contact stress. However, gait analysis demonstrated that factors other than alignment contributed significantly to the outcome of corrective surgery. It was therefore hypothesized that muscle contraction can alter the stress distribution within the knee joint and that overloading can occur in the absence of a deformity. Six normal knees were harvested from different donors. The exact orientation of all muscle groups was recorded and their tendinous insertions carefully preserved. Custom built pressure transducers (6 per compartment, 0.5 mm thick, 10 mm diameter) were inserted through 2 small, posterior, capsular incisions and placed on the tibial surface and the menisci. The knees were mounted in a loading system which allowed free self-alignment of the joint under load. All muscles were replaced by wire cables instrumented with force transducer, tensioner and grip. Several alignment models (5, 10 degree varus, neutral, 5 degree valgus and 15 degree of flexion) as well as the effect of contraction of all major muscles crossing the knee joint were tested. An even pressure distribution was seen in neutral alignment. In a varus deformity the peak pressure shifted medially and laterally in valgus. Unloading of the opposite compartment was seen for deformities as small as 5 degrees. A flexion deformity produced a postero-lateral shift of the peak pressure area. Muscle contraction increased the pressure significantly in a region next to the muscle. Generally, unloading - though less significant - was seen in a region diagonally across the joint. These results suggest that muscular hyperactivity may considerable increase the contact stresses. However, muscle weakness or lack of muscular contraction may indirectly play a significant role in affecting the contact pressure distribution. If the muscle force is insufficient to counterbalance the external moment condylar lift-off occurs. This increases the angulation between femur and tibia thereby overloading the compartment where contact takes place; One can therefore conclude that abnormal gait patterns or neuromuscular control mechanisms may result in unphysiologically high contact stresses which may cause the development of unicompartmental osteoarthritis and subsequently, a deformity.

Macrophages are an important cell type well known for its’ role in the immune system. Macrophages have two hematopoietic sources; they can be derived from hematopoietic stem cell (HSC) progenitors or erythro-myeloid progenitors (EMP). Synovial macrophages exist within the normal healthy joint, but the current origins and functions of these cells are unclear, including those involved in inflammatory arthritis (IA). To explore the origins of the synovial macrophages we utilized both cell lineage-tracing models and an arthritic model, K/BxN mice serum transfer arthritis (STA). We used Flt3Cre;Rosa26LSL-YFP mice to label HSC-derived cells and Cx3cr1CreERT2;Rosa26LSL-tdTomato and CSF1rmericremer;Rosa26LSL-tdTomato mice to label EMP-derived cells. Our histological data showed a unique population of EMP derived synovial tissue resident macrophages that was present in mice at ages E16.5 and P0 (neonate). Additionally, we found that HSC-derived cells do not significantly contribute to synovial macrophage populations throughout development. Interestingly, in arthritic conditions, we detected a dramatic increase in HSC-derived synovial macrophages in the inflamed synovium. Using macrophage markers F4/80 and CD68 we were able to fluorescently label and identify three different subtypes of synovial macrophages that exist within the joint in both homeostatic and arthritic conditions. Although further studies need to be completed, we have taken a pivotal step towards characterizing synovial macrophages in healthy and arthritic mice.