Ian McCarthy

Analysis of knee flexion characteristics and how they alter with the onset of knee osteoarthritis: a case control study

BackgroundThe purpose of this study was to examine the differences in gait profile between patients with knee osteoarthritis (OA) and healthy control and to create motion characteristics that will differentiate between them.MethodsTwenty three patients diagnosed with knee OA and 21 healthy matched controls underwent a gait test using a sensor system (gaitWALK). Gait parameters evaluated were: stride duration, knee flexion range of motion (ROM) in swing and stance. T-Test was used to evaluate significant differences between groups (Pu2009<u20090.05).ResultsPatients with knee OA had significant lower knee flexion ROM (10.3°u2009±u20094.0°) during stance than matched controls (18.0°u2009±u20094.0°) (pu2009<u20090.001). Patients with knee OA had significant lower knee flexion ROM (54.8°u2009±u20095.5°) during swing than matched controls (61.2°u2009±u20096.1) (pu2009=u20090.003). Patients with knee OA also had longer stride duration (1.12u2009su2009±u20090.09u2009s) than matched controls (1.06u2009su2009±u20090.11u2009s), but this was not statistically significant (pu2009=u20090.073). Motion characteristics differentiate between a patient with knee OA and a healthy one with a sensitivity of 0.952 and a specificity of 0.783.ConclusionsSignificant differences were found in the gait profile of patients with knee OA compared to matched control and motion characteristics were identified. This test might help clinicians identify and evaluate a knee problem in a simple gait test.

Gait assessment as a functional outcome measure in total knee arthroplasty: a cross-sectional study

BackgroundThe aim of the study was to assess gait in total knee arthroplasty (TKA) patients, using a technique that can to be used on a routine basis in a busy orthopaedic clinic.MethodsA total of 103 subjects were recruited: 29 pre-op TKA patients; 17 TKA patients at 8xa0weeks post-op; 28 TKA patients at 52xa0weeks post-op; and 29 age-matched controls. Inertial measurement units (IMUs) were used to assess gait. Limb segment angles, knee angle and temporal parameters of gait were calculated. Specific gait parameters were quantified, and data analysed using MANOVA and discriminant analysis.ResultsThe gait of TKA patients as a group was only slightly improved at 12xa0months when compared with the pre-operative group, and both groups were significantly different to controls in several variables. Knee flexion range in stance was the most important variable in discriminating between patients and controls; knee flexion range in swing was the only variable that showed a significant difference between pre- and post-operative patients. When considered individually, only 1/29 patient was within the normal range for this variable pre-operatively, but 9/28 patients were within the normal range 12xa0months post-operatively.ConclusionsEven after 12xa0months after surgery, many TKA patients have not improved their gait relative to pre-operative patients. Routine gait assessment may be used to guide post-operative rehabilitation, and to develop strategies to improve mobility of these patients.

Evidence from Raman Spectroscopy of a Putative Link Between Inherent Bone Matrix Chemistry and Degenerative Joint Disease

Osteoarthritis (OA) is a common debilitating disease that results in degeneration of cartilage and bone in the synovial joints. Subtle changes in the molecular structure of the subchondral bone matrix occur and may be associated with cartilage changes. The aim of this study was to explore whether the abnormal molecular changes observed in the matrix of OA subchondral bone can be identified with Raman spectroscopy.