Bariatric Surgery on Short Term Weight Loss- Related Changes in Gait

• Body Composition, describes change in body composition from pre-op levels [ Time Frame: Describes change over a period of 4 weeks; measured at pre-op, 2 and 4 weeks following surgery ] [ Designated as safety issue: No ]
  To track changes in body composition and mass during the study, body weight body fat mass, fat free mass will be collected prior to and 2 and 4 weeks after the bariatric surgery using air plethysmography. Air plethysmography (using the BOD POD®) is a reliable technique of body volume and composition, and has been validated for use in obese individuals and is highly correlated to the gold standard of body composition assessment, underwater weighing.
  
  

• Gait Analysis, describes change in gait parameters from pre-op levels [ Time Frame: Describes changes in gait parameters over a 3 month period; measured at pre-op, 4 weeks and 3 months following surgery. ] [ Designated as safety issue: No ]
  The gait analysis involves walking on a 26' long portable gait mat (GaitRite®). The mat is a cushioned thin mat filled with pressure sensors. Participants will be asked to walk at a self-selected, comfortable pace across the 26 foot long mat. This normal self-selected pace will be performed three times and the values will be averaged for the three trials. The participant will then be asked to walk as quickly as possible across the mat and the velocity to reach 20' will be determined. This will be repeated two more times for a total of 3 trials.
  
  
• Lower Extremity Joint Pain, describes change from pre-op using a Visual Analog Scale (VAS). [ Time Frame: Describes change in lower extremity joint pain over a period of 3 months; measured with a (VAS) at per-op, 4 weeks and 3 months following surgery ] [ Designated as safety issue: No ]
  Joint pain intensity will be self-assessed by a 10 cm (VAS) with terminal descriptors (anchors of 0 cm = no pain; 10 cm = worst possible pain). The (VAS) is an accepted outcome measure for chronic pain.
  
  
• Medical Outcomes Short Form (SF-36), describes change in perceived quality of life (QOL) [ Time Frame: Describes perceived (QOL) over a period of 3 months, measured at pre-op, 4 weeks and 3 months following surgery ] [ Designated as safety issue: No ]
  The (SF36) is an instrument that assesses overall health-related (QOL). The (SF36) is comprised of eight subscales, each ranging from 0-100 points, with higher scores representing better health. The (SF36) has been recommended for use following bariatric surgery to capture meaningful changes in (QOL).
  
  

This is a prospective, exploratory, short term study of the effects of bariatric surgery on body composition, gait parameters during walking, lower extremity joint pain and quality of life (QOL) in morbidly obese patients. All patients who enroll have already agreed to undergo the bariatric procedure with their respective surgeon; the study team will simply follow specific outcome measures in addition to their normal clinical care at two time points after the surgery (week 4 and month 3).