1. A method of measuring surgical parameters in computer-assisted surgery so as to guide an operator in inserting a hip joint implant in a femur, comprising:
i) digitizing a frame of reference of a pelvis, the frame of reference of the pelvis being trackable in space;
ii) digitizing a pre-reduction frame of reference of the femur as a function of the frame of reference of the pelvis, the pre-reduction frame of reference comprising a femoral axis;
iii) obtaining a reference orientation for the femoral axis of the pre-reduction frame of reference of the femur with respect to the frame of reference of the pelvis;
iv) digitizing a reduction frame of reference of the femur by virtually orienting the femoral axis in said reference orientation as a function of the frame of reference of the pelvis, after initiation of implant reduction;
v) providing the surgical parameters associating the femur to the pelvis and measured as a difference between the first and second frames of reference of the femur.
2. The method according to claim 1, wherein the femoral axis is a mechanical axis, and wherein obtaining a the reference orientation comprises the reference orientation having the mechanical axis of the pre-reduction frame of reference of the femur at a predetermined angle of a vertical axis of a patient within a frontal plane of the frame of reference of the pelvis.
3. The method according to claim 2, wherein obtaining the reference orientation comprises the reference orientation having the mechanical axis where the predetermined angle is 3\xb0.
4. The method according to claim 2, wherein digitizing the frame of reference of the pelvis comprises digitizing two points on an iliac crest and a point on one of pubic tubercles to obtain the frontal plane of the frame of reference of the pelvis.
5. The method according to claim 2, wherein obtaining the reference orientation comprises having the mechanical axis of the pre-reduction frame of reference of the femur pass through a center of rotation of the femur, and the reference orientation has the center of rotation of the femur and of an acetabulum coincident.
6. The method according to claim 1, wherein the step iv) includes updating the frame of reference of the pelvis by digitizing a center of rotation of the acetabulum subsequently to the implant reduction.
7. The method according to claim 1, wherein the surgical parameters are at least one of a limb length discrepancy and a medio-lateral offset.
8. The method according to claim 1, wherein the steps i) and ii) are performed with respect to a single trackable reference secured to the pelvis.
9. The method according to claim 1, wherein the method is performed on a bone model or a cadaver.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A health management apparatus comprising:
a first pulse wave measuring unit that measures a first pulse wave of a subject during sleep;
a second pulse wave measuring unit that measures a second pulse wave of the subject during sleep, the second pulse wave being different from the first pulse wave in propagation time from the heart of the subject;
a pulse transmission time calculating unit that calculates a pulse transmission time indicating a time difference between the first pulse wave and the second pulse wave;
a pulse interval calculating unit that calculates a pulse interval based on at least one of the first pulse wave and the second pulse wave;
an autonomic nerve index calculating unit that calculates an autonomic nerve index indicating an autonomic nerve activity of the subject based on the pulse transmission time and the pulse interval; and
a health determining unit that determines the condition of health of the subject based on the autonomic nerve index.
2. The health management apparatus according to claim 1, further comprising a health output unit that outputs the condition of health.
3. The health management apparatus according to claim 1, wherein the health determining unit determines a sleep state based on the autonomic nerve index.
4. The health management apparatus according to claim 3, wherein the health determining unit determines whether the sleep is REM sleep or non-REM sleep based on the autonomic nerve index.
5. The health management apparatus according to claim 1, wherein the autonomic nerve index calculating unit calculates the autonomic nerve index in a low-frequency region based on the pulse transmission time.
6. The health management apparatus according to claim 1, further comprising a pressure sensor that detects pressure from the body weight of the subject,
wherein the first pulse wave measuring unit measures the first pulse wave based on the pressure detected by the pressure sensor.
7. A health management apparatus comprising:
a first pulse wave measuring unit that measures a first pulse wave of a subject during sleep;
a second pulse wave measuring unit that measures a second pulse wave of the subject during sleep, the second pulse wave being different from the first pulse wave in propagation time from the heart of the subject;
a pulse transmission time calculating unit that calculates a pulse transmission time indicating a time difference between the first pulse wave and the second pulse wave;
a pulse interval calculating unit that calculates a pulse interval based on at least one of the first pulse wave and the second pulse wave;
an autonomic nerve index calculating unit that calculates an autonomic nerve index indicating an autonomic nerve activity of the subject based on the pulse transmission time and the pulse interval;
a blood pressure value calculating unit that calculates a blood pressure value based on the pulse transmission time; and
a health determining unit that determines the condition of health of the subject based on the autonomic nerve index and the blood pressure value.
8. The health management apparatus according to claim 7, further comprising:
a blood pressure variability pattern storing unit that stores a blood pressure variability pattern indicating a time variation in blood pressure during sleep; and
a pattern comparing unit that compares the time variation in blood pressure during sleep with the blood pressure variability pattern,
wherein the health determining unit determines the condition of health of the subject based on the comparison result.
9. The health management apparatus according to claim 8, further comprising a sleep determining unit that determines whether the sleep is REM sleep or non-REM sleep based on the autonomic nerve index,
wherein the pattern comparing unit compares the time variation in blood pressure during sleep with the blood pressure variability pattern, the blood pressure during sleep being obtained when the sleep determining unit detects REM sleep.
10. The health management apparatus according to claim 7, further comprising a basal blood pressure determining unit that determines a basal blood pressure to be a minimum value in the time variation of the blood pressure value,
wherein the health determining unit determines the condition of health based on the basal blood pressure.
11. The health management apparatus according to claim 7, further comprising:
a sleep determining unit that determines whether the sleep is REM sleep or non-REM sleep based on the autonomic nerve index; and
a basal blood pressure determining unit that determines a basal blood pressure to be a minimum value of the blood pressure obtained when the sleep determining unit detects REM sleep,
wherein the health determining unit determines the condition of health based on the basal blood pressure.
12. The health management apparatus according to claim 10, further comprising:
a wake-up determining unit that determines whether the subject has woken up based on the autonomic nerve index; and
a wake-up time blood pressure increase rate calculating unit that calculates a blood pressure increase rate from the basal blood pressure to the blood pressure value obtained when the subject is determined to has waken up,
wherein the health determining unit determines the condition of health of the subject based on the blood pressure increase rate.
13. The health management apparatus according to claim 11, further comprising:
a wake-up determining unit that determines whether the subject has woken up based on the autonomic nerve index; and
a wake-up time blood pressure increase rate calculating unit that calculates a blood pressure increase rate from the basal blood pressure to the blood pressure value obtained when the subject is determined to has waken up,
wherein the health determining unit determines the condition of health of the subject based on the blood pressure increase rate.
14. The health management apparatus according to claim 10, further comprising:
a sleep determining unit that determines whether the sleep is REM sleep or non-REM sleep based on the autonomic nerve index; and
an early-morning blood pressure increase rate calculating unit that calculates a blood pressure increase rate from the basal blood pressure to the blood pressure value obtained when the last non-REM sleep during the sleep is detected,
wherein the health determining unit determines the condition of health of the subject based on the blood pressure increase rate.
15. The health management apparatus according to claim 7, further comprising a pulse transmission time variation measuring unit that measures a variation in a predetermined period of time within the pulse transmission time,
wherein the health determining unit determines the condition of health of the subject based on a result of the measurement by the pulse transmission time variation measuring unit.
16. The health management apparatus according to claim 7, further comprising a pressure sensor that detects pressure from the body weight of the subject,
wherein the first pulse wave measuring unit measures the first pulse wave based on the pressure detected by the pressure sensor.
17. A health management apparatus comprising:
an electrocardiogram activity measuring unit that measures the degree of an electrocardiogram activity of a subject during sleep;
a first pulse wave measuring unit that measures a first pulse wave of the subject during sleep;
a pulse transmission time calculating unit that calculates a pulse transmission time indicating a time difference between the electrocardiogram activity and the first pulse wave;
a pulse interval calculating unit that calculates a pulse interval based on at least one of the degree of the electrocardiogram activity and the first pulse wave;
an autonomic nerve index calculating unit that calculates an autonomic nerve index indicating an autonomic nerve activity of the subject based on the pulse transmission time and the pulse interval; and
a health determining unit that determines the condition of health of the subject based on the autonomic nerve index.
18. A health management apparatus comprising:
an electrocardiogram activity measuring unit that measures the degree of an electrocardiogram activity of a subject during sleep;
a first pulse wave measuring unit that measures a first pulse wave of the subject during sleep;
a pulse transmission time calculating unit that calculates a pulse transmission time indicating a time difference between the electrocardiogram activity and the first pulse wave;
a pulse interval calculating unit that calculates a pulse interval based on at least one of the degree of the electrocardiogram activity and the first pulse wave;
an autonomic nerve index calculating unit that calculates an autonomic nerve index indicating an autonomic nerve activity of the subject based on the pulse transmission time and the pulse interval;
a blood pressure value calculating unit that calculates a blood pressure value based on the pulse transmission time; and
a health determining unit that determines the condition of health of the subject based on the autonomic nerve index and the blood pressure value.
19. A health management system comprising a health management main apparatus and a health management sub apparatus that manage the condition of health of a subject,
the health management sub apparatus comprising:
a first pulse wave measuring unit that measures a first pulse wave of the subject during sleep; and
a transmission unit that transmits the first pulse wave to the health management main apparatus,
the health management main apparatus comprising:
a reception unit that receives the first pulse wave from the health management sub apparatus;
a second pulse wave measuring unit that measures a second pulse wave of the subject during sleep, the second pulse wave being different from the first pulse wave in propagation time from the heart of the subject;
a pulse transmission time calculating unit that calculates a pulse transmission time indicating a time difference between the first pulse wave and the second pulse wave;
a pulse interval calculating unit that calculates a pulse interval based on at least one of the first pulse wave and the second pulse wave;
an autonomic nerve index calculating unit that calculates an autonomic nerve index indicating an autonomic nerve activity of the subject based on the pulse transmission time and the pulse interval; and
a health determining unit that determines the condition of health of the subject based on the autonomic nerve index.
20. A health management system comprising a health management main apparatus and a health management sub apparatus that manage the condition of health of a subject,
the health management sub apparatus comprising:
a first pulse wave measuring unit that measures a first pulse wave of the subject during sleep; and
a transmission unit that transmits the first pulse wave to the health management main apparatus,
the health management main apparatus comprising:
a reception unit that receives the first pulse wave from the health management sub apparatus;
a second pulse wave measuring unit that measures a second pulse wave of the subject during sleep, the second pulse wave being different from the first pulse wave in propagation time from the heart of the subject;
a pulse transmission time calculating unit that calculates a pulse transmission time that is the time difference between the first pulse wave and the second pulse wave;
a pulse interval calculating unit that calculates a pulse interval based on at least one of the first pulse wave and the second pulse wave;
an autonomic nerve index calculating unit that calculates an autonomic nerve index indicating an autonomic nerve activity of the subject based on the pulse transmission time and the pulse interval;
a blood pressure value calculating unit that calculates a blood pressure value, based on the pulse transmission time; and
a health determining unit that determines the condition of health of the subject based on the autonomic nerve index and the blood pressure value.
21. A health management method comprising:
measuring a first pulse wave of a subject during sleep;
measuring a second pulse wave of the subject during sleep, the second pulse wave being different from the first pulse wave in propagation time from the heart of the subject;
calculating a pulse transmission time indicating a time difference between the first pulse wave and the second pulse wave;
calculating a pulse interval, based on at least one of the first pulse wave and the second pulse wave;
calculating an autonomic nerve index indicating an autonomic nerve activity of the subject based on the pulse transmission time and the pulse interval; and
determining the condition of health of the subject, based on the autonomic nerve index.
22. A health management method comprising:
measuring a first pulse wave of a subject during sleep;
measuring a second pulse wave of the subject during sleep, the second pulse wave being different from the first pulse wave in propagation time from the heart of the subject;
calculating a pulse transmission time indicating a time difference between the first pulse wave and the second pulse wave;
calculating a pulse interval based on at least one of the first pulse wave and the second pulse wave;
calculating an autonomic nerve index indicating an autonomic nerve activity of the subject based on the pulse transmission time and the pulse interval;
calculating a blood pressure value, based on the pulse transmission time; and
determining the condition of health of the subject, based on the autonomic nerve index and the blood pressure value.
23. A computer program product having a computer readable medium including programmed instructions for managing health, wherein the instructions, when executed by a computer, cause the computer to perform:
measuring a first pulse wave of a subject during sleep;
measuring a second pulse wave of the subject during sleep, the second pulse wave being different from the first pulse wave in propagation time from the heart of the subject;
calculating a pulse transmission time indicating a time difference between the first pulse wave and the second pulse wave;
calculating a pulse interval, based on at least one of the first pulse wave and the second pulse wave;
calculating an autonomic nerve index indicating an autonomic nerve activity of the subject based on the pulse transmission time and the pulse interval; and
determining the condition of health of the subject, based on the autonomic nerve index.
24. A computer program product having a computer readable medium including programmed instructions for managing health, wherein the instructions, when executed by a computer, cause the computer to perform:
measuring a first pulse wave of a subject during sleep;
measuring a second pulse wave of the subject during sleep, the second pulse wave being different from the first pulse wave in propagation time from the heart of the subject;
calculating a pulse transmission time indicating a time difference between the first pulse wave and the second pulse wave;
calculating a pulse interval based on at least one of the first pulse wave and the second pulse wave;
calculating an autonomic nerve index indicating an autonomic nerve activity of the subject based on the pulse transmission time and the pulse interval;
calculating a blood pressure value, based on the pulse transmission time; and
determining the condition of health of the subject, based on the autonomic nerve index and the blood pressure value.