This invention relates generally to adjustable chairs, and in particular to adjustable chairs for supporting bariatric patients undergoing medical or dental treatment.

It is known that for patients undergoing medical or dental examinations, it is convenient to provide a chair in which a patient can easily assume a position to facilitate examination by a medical or dental professional. For example, for a dental examination or procedure, it is ideal for a patient to be able to recline with their head tilted back to allow a dentist easily to examine their teeth. It is also desirable for a patient to easily seat themselves on such a chair, and to easily adopt a standing position from the chair once the treatment or examination is complete. It is known for existing treatment chairs to be adjustable, for example, to be adjustable from an upright seating position to a reclining position while the patient is seated in the chair, or to be adjustable in height. Conventional treatment chairs also allow the patient freedom of movement to shift their body position in the chair once seated or reclining, for example to improve their comfort or to allow the medical or dental professional to conduct the examination or treatment more easily.

However, the population has an increasing proportion of overweight and obese people. There is a group of patients who are seriously obese, i.e. bariatric patients, who have some limited mobility but do not consider themselves to be disabled and do not regularly use a wheelchair. Such bariatric patients can find it difficult or impossible to seat themselves in a conventional dental or medical chair, or to adjust their position once they are seated to allow a medical or dental practitioner to conduct an examination or treatment.

There is thus a need for a treatment chair that allows bariatric patients to seat themselves with greater ease, and which allows the adjustment of a bariatric patient's position once he or she is seated. A particular problem with conventional treatment chairs is that the adjustable components (in particular, the arm rests) are connected to the seat or back rest of the chair by hinged connections or other adjustable connecting means that are typically not robust enough to support the weight of a bariatric patient. Bariatric patients attempting to seat themselves in a conventional treatment chair (or stand up having been seated in a conventional treatment chair) risk causing damage to the arm rests of the chair as they lift themselves into or out of the seat. They also risk causing the chair to tip over if they lean their weight onto one of the arm rests. There is thus a need for an improved treatment chair.

According to a first aspect of the invention, there is provided an adjustable chair comprising a seat to accommodate a person, a base to rest on a ground surface in use, left and right arm rests, height-adjusting means for adjusting a vertical position of the seat and the arm rests relative to the base, and left and right support members configured respectively to directly transmit a force applied to the left and right arm rests to the ground surface.

According to a second aspect of the invention, there is provided an adjustable chair comprising a seat to accommodate a person, a base to rest on a ground surface in use, left and right arm rests, and left and right support members configured respectively to directly transmit a force applied to the left and right arm rests and/or to the seat to the ground surface, wherein the left and right support members comprise height-adjusting means for adjusting a vertical position of the seat and the arm rests relative to the base.

It will be understood that the support members being configured to directly transmit a force to the ground has the meaning that the force is transmitted from the point at which the force is exerted on the support member (either by an arm rest and/or by the seat) directly to the ground. Such force transmission may, preferably, act vertically downwards through the support members. It will be further understood that the transmission of a force via the base to the ground surface also falls within the meaning of the force being directly transmitted to the ground. Such a chair therefore has stability provided by transmitting central forces on the seat to the left and right support members. Furthermore, as the left and right support members directly transmit the force applied to the left and right arm rests to the ground, the arm rests can withstand significant weight being applied to them. A bariatric patient is therefore able to lift himself or herself into or out of the seat by exerting a force on the left and right arm rests. In contrast, the arm rests of conventional treatment chairs, which are typically connected to the seat or a back rest of the chair, are not able to support high force and would likely be damaged by the weight applied to them as a bariatric patient lifts him or herself into or out of the seat. Further, as support members are provided on the left and right sides of the adjustable chair and in contact with the ground surface, there is a reduced chance of the chair tilting or tipping over due to, for example, a patient applying his or her weight unevenly to the arm rests. Thus the adjustable treatment chair of the present invention is more robust and more stable than conventional treatment chairs.

In embodiments according to the first aspect of the invention, the height-adjusting means may be configured to adjust the height of the chair by applying a force to any suitable part of the chair, for example, the seat (e.g. directly underneath the seat). However, preferably the height adjusting-means is configured to adjust the vertical position of the seat and the arm rests relative to the base by applying forces directly to the left and right arm rests. In accordance with the second aspect, and in preferred embodiments of the first aspect, the left and right support members comprise height adjusting-means configured to adjust the vertical position of the seat and the arm rests relative to the base by applying forces directly to the left and right arm rests and/or to the seat. Additional height-adjusting means may optionally be configured to adjust the height of the seat by applying a force to any suitable part of the seat.

Thus, in accordance with the invention, an adjustable chair may be provided with height-adjusting means beneath the arms rests but not beneath the seat, or beneath the seat but not beneath the arm rests, or beneath the arm rests and beneath the seat, or in other configurations. Where height-adjusting means are provided beneath the arm rests but not beneath the seat, as is preferred, preferably the height-adjusting means are configured so as also to adjust the height of the seat. Preferably no separate height-adjusting means is provided to apply a force directly to the seat. Preferably the seat is carried with the arm rests when the height-adjustment means adjusts the height of the arm rests. Preferably, a supportive collar is provided on (e.g. attached to or integrated with) each of the height-adjusting means, where the collar is arranged to transmit forces applied to the seat to the height-adjusting means. For example, an annular collar may be provided attached to or integrated with each height-adjusting means (i.e. support member), with the seat configured to rest on the supportive collar. Such a supportive collar may thereby support the weight of that seat and of the patient on the seat and/or effect the height adjustment of the seat by the height-adjusting means.

The height-adjusting means preferably provides continuous height adjustment. The height-adjusting means may have a controllable speed of adjustment. In addition to being supported by the left and the right support members, the left and right arm rests may be attached to the seat of the chair. In some

embodiments, the arm rests are integral with the seat. This increases the strength of the chair and its ability to support very large weights. The left and right support members may be provided in any configuration that allows them to transmit a force applied to the left and right arm rests to the ground surface, however in a preferred embodiment the left and right support members are disposed beneath respectively the left and right arm rests. This allows the support members to transmit forces applied to the arm rests directly to the ground.

Preferably, the support members are disposed directly beneath the arm rests. It will be understood by one skilled in the art that the support members being "beneath the arm rests" has the meaning of at least a portion of each support member is in vertical alignment with at least a portion of the respective arm rest, and being generally closer to the ground surface than the arm rest. It will be further understood that "directly beneath" has the meaning of substantially all of the support member being in vertical alignment with a least a portion of the arm rest, and being generally closer to the ground surface than the arm rest, such that the forces transmitted from the arm rest to the ground surface via the support member are transmitted in a substantially vertical plane.

In accordance with the first aspect, the support members remain configured to transmit forces applied to the arm rests to the ground surface irrespective of the height of the adjustable chair. This may be achieved, for example, by providing extendable support members that extend or contract as the height of the chair is adjusted. For example, the support members may be telescopic columns. In accordance with the second aspect, and preferred embodiments of the first aspect, the support members comprise the height-adjusting means. This is advantageous as there is no need to provide separate support members to transmit weight applied to the arm rests to the ground. The height adjusting means thus provides a dual function of adjusting the height of the chair and supporting the weight of the patient. However, additional, separate support members could be provided. Such additional support members would remain configured to transmit forces applied to the arm rests to the ground surface irrespective of the height of the adjustable chair. This may be achieved, for example, by providing extendable support members that extend or contract as the height of the chair is adjusted. For example, the support members or additional support members may be telescopic columns. Any suitable height-adjusting means may be used. For example, mechanical or pneumatic height-adjusting means may be used, however in preferred

embodiments, the height-adjusting means comprises hydraulic rams. Hydraulic rams are particularly suitable as they are rigid and weight-bearing. The hydraulic rams may be integral with the arm rests. Preferably the height-adjusting means is electrically driven. This is advantageous as it allows the height-adjusting means to be remotely controlled.

In addition, or alternatively, the adjustable chair may be provided with a back rest. In some embodiments, the adjustable chair comprises a back rest; pivotal adjustment means for pivotally adjusting a position of the back rest between a substantially upright position and a reclining position; and linear adjustment means for varying a distance of the back rest from the seat. Preferably, the linear adjustment means and the pivotal adjustment means are coupled to produce simultaneous, corresponding linear and pivotal movement of the back rest.

The back rest may therefore be pivotally adjusted to change the patient's seated position into a reclining position for, for example, a medical or dental treatment or examination. The back rest may be adjusted linearly to vary the height of the back rest relative to the seat to increase patient comfort and/or to accommodate patients of different heights. In some embodiments, the simultaneous, corresponding linear and pivotal movement of the back rest is in accordance with a predetermined ratio of pivotal movement to linear movement. This movement in a predetermined ratio can prevent or reduce sliding between the patient's back and the back support. This is particularly important for bariatric patients who, as a result of their bariatric condition, may be less capable of adjusting their position to alleviate any discomfort due to sliding between the back rest and their skin, and who may have sensitive or delicate skin that would be easily injured by friction or sliding between their skin and the back rest. The back rest may be electrically driven. The linear adjustment means and the pivotal adjustment means may be coupled by any suitable coupling means, for example, mechanical or electrical coupling means. However, preferably the linear adjustment means and the pivotal adjustment means are coupled by an electronic controller configured to move the pivotal and linear adjustment means in accordance with a predetermined correspondence between linear and pivotal movement.

In addition, or alternatively, the adjustable chair may comprise a foot rest. It will be understood by one skilled in the art that a foot rest may be any suitable

arrangement for supporting the feet and/or lower legs of a patient. In some embodiments, the adjustable chair comprises a foot rest; pivotal adjustment means for pivotally adjusting a position of the foot rest between a lowered position and an elevated position; and linear adjustment means for varying a distance of the foot rest from the seat. The linear adjustment means may be, for example, an electrical linear drive or mechanical adjustment means. Preferably, the linear adjustment means and the pivotal adjustment means are coupled to produce simultaneous, corresponding linear and pivotal movement of the foot rest. In some embodiments, the simultaneous, corresponding linear and pivotal movement of the foot rest is in accordance with a predetermined ratio of pivotal movement to linear movement. In particular, when the foot rest is pivoted to support the patient's feet in an elevated position, the foot rest may extend to prevent sliding between the patient's leg and the foot rest. Similarly, when the foot rest is pivoted to return the patient's feet from an elevated position to the ground, the foot rest may retract. This is advantageous as it helps to reduce injury or discomfort to the legs of the patient, who, due to their bariatric condition, may have delicate or sensitive skin or may be less capable of moving their legs to prevent sliding between their legs and the foot rest. The foot rest may be electrically driven. The linear adjustment means and the pivotal adjustment means may be coupled by any suitable coupling means, for example, mechanical or electrical coupling means. However, preferably the linear adjustment means and the pivotal adjustment means are coupled by an electronic controller configured to move the pivotal and linear adjustment means in accordance with a predetermined correspondence between linear and pivotal movement.

The adjustable chair may be provided with an articulated head rest.

Remote controlling means may be provided for remotely adjusting the chair, for example, by electrical control of the height-adjusting means. The remote controlling means may be an infra-red hand held remote, or foot-operated switches. The adjustable chair may also be provided with means for moving the chair within a surgery or between surgeries. The means for moving the chair may be, for example, ball bearing castor pods that are incorporated into the base, and supplied by a pneumatic pump mounted on the base. Control of the pressure of supplied air provides suspension and ensures even loading on the castors. This ball bearing castor pod arrangement is described in United Kingdom Patent No. 2454933, which is incorporated by reference herein.

A preferred embodiment of the present invention will now be described, by way of example only, and with reference to the accompanying drawings, in which: Figure 1 shows a perspective view of a first embodiment of an adjustable treatment chair in accordance with the present invention.

Figure 2 shows a side view of the adjustable treatment chair of Figure 1. Figure 3 shows a perspective view of the adjustable treatment chair of Figure 1 with the foot rest in an elevated position and with the height-adjusting means extended to elevate the chair.

Figure 4 shows a side view of the adjustable treatment chair in the position shown in Figure 3, with the foot rest extended. Figure 5 shows a perspective view of the adjustable treatment chair of Figure 1 in a reclined position, and with the height-adjusting means extended to elevate the chair.

Figure 6 shows a side view of the treatment chair of Figure 1 in a reclined position and with the height-adjusting means retracted to lower the chair.

Figure 7 shows a rear perspective view of an adjustable back rest for an adjustable treatment chair in accordance with the first embodiment, with its back cover removed to show the internal components.

Figure 8 shows a side view of an adjustable back rest and articulated head rest for an adjustable treatment chair in accordance with the first embodiment.

Figure 9 shows a rear perspective view of the adjustable chair of Figure 1.

Figure 10 shows a perspective view of a second embodiment of an adjustable treatment chair in accordance with the present invention.

Figure 11 shows a side view of the adjustable treatment chair of Figure 10.

Figure 12 shows a cross section of a schematic representing one of the arm rests and the corresponding support member of the second embodiment.

Figure 13 shows a side view of the treatment chair of Figure 10 in a reclined position and with the height-adjusting means retracted to lower the chair.

Figure 14 shows a rear perspective view of an adjustable back rest for an adjustable treatment chair in accordance with the second embodiment, with its back cover removed to show the internal components.

Figure 15 shows a rear perspective view of the adjustable chair of Figure 10. Figure 16 shows a perspective view of the foot rest of the embodiment of Figure 10 with the foot rest in an elevated position.

Figures 1 and 2 show a first embodiment of an adjustable treatment chair 2 in accordance with the present invention. The adjustable treatment chair 2 comprises a seat 4, a base 6, left 8 and right 10 arm rests, left 12 and right 14 support members, which also serve as height-adjusting means, an adjustable back rest 16, an adjustable foot rest 18, an articulated head rest 20, and a telescopic support member 22 underneath the seat 4.

The left 12 and right 14 support members are disposed directly beneath the left 8 and right 10 arm rests. The support members 12, 14 may be formed from any suitable rigid material. When a bariatric patient applies weight to the arm rests 8, 10 as he or she lowers him or herself into the chair 2, the support members 12, 14 transmit the weight applied to the arm rests 8, 10 directly to the ground. In the present embodiment, the support members 12, 14 are in the form of hydraulic rams, and thus also serve as height-adjusting means for the chair. This dual function is advantageous as there is no need to provide separate weight- bearing support members for each arm rest 8, 10.

A telescopic weight-bearing support 22 is provided underneath the seat 4 of the chair 2, which supports some or all of the patient's weight while the patient is seated in the chair 2. Additional height-adjusting means could be provided underneath the seat 4, in addition to or instead of the telescopic support 22.

However, in the present embodiment, the telescopic support 22 does not perform the function of a height-adjusting means. In alternative embodiments, a non- weight-bearing cover may be provided in the place of the weight-bearing support 22, or a support 22 beneath the seat 4 may be omitted entirely. For example, a telescopic cover may be provided for aesthetic purposes to cover a controller that operates the hydraulic rams underneath the arm rests.

In embodiments where there is no weight-bearing support or height-adjusting means provided under the seat, the weight of the seat and the patient in the seat may be fully supported by the support members via a supportive collar on each support member, on which the seat rests. Such supportive collars are described below with reference to the second embodiment shown in Figures 10-16.

Figures 3 and 4 show the adjustable chair 2 of the first embodiment, where the height-adjusting means 12, 14 is extended such that the chair 2 is in an elevated position. The telescopic support 22 under the seat 4 is extended to provide support for a patient's weight transmitted through the seat 4.

The foot rest 18 has been pivotally adjusted with respect to its position as shown in Figures 1 and 2 into a horizontal position to support the patient's legs in an elevated position. In Figure 4, the foot rest 18 has also been extended by a distance d. The extension of the foot rest 18 is achieved using an hydraulic ram 24, although it could instead be achieved by, for example, a mechanical linkage or an electrical linear drive. The extension of the foot rest 18 is performed during the pivotal movement of the foot rest 18 from a vertical position as shown in Figures 1 and 2 to a horizontal position as shown in Figures 3 and 4. The extension is varied with angular displacement of the foot rest 18 such that there is no sliding between the surface of the foot rest 18 and the patient's legs. This reduces the risk of injury or discomfort to the patient's skin that may be caused by the foot rest 18 sliding over the patient's legs.

The back rest 16 is shown in a substantially upright position and a hydraulic ram or linear drive (described below with reference to Figure 7) is provided to facilitate extension of the back rest. If, for example, a short patient or a child is to be accommodated in the chair 2, the back rest 16 can be retracted to bring the back rest 16 closer to the seat 4 to accommodate the patient's shorter stature. On the other hand, if a tall patient is to be accommodated, the back rest 16 can be extended to adjust for the patient's taller stature. The hydraulic rams 12, 14 in the present embodiment are electrically driven. Figure 5 shows the adjustable chair of the first embodiment with the hydraulic rams 12, 14 extended so that the chair 2 is in an elevated position. The back rest 16 is in a reclining position, and the foot rest 18 is in an elevated position so that the chair 2 provides a horizontal surface for a bariatric patient to lie on during examination or treatment. Figure 6 shows the adjustable chair of the first embodiment with the hydraulic rams 12, 14 retracted so that the chair 2 is in a lowered position, while the back rest 16 is reclined and the foot rest 18 is elevated to provide a horizontal surface for the patient to lie on. Depending on the treatment or examination the patient is undergoing, a lowered reclining position may be more suitable than an elevated reclining position, or vice versa.

Figure 7 shows the back rest 16 of the adjustable chair 2 with the back cover removed so that the internal components are visible. The back rest 16 includes stainless steel support tubes 32 on which the back rest 16 is slidably mounted. A linear drive 34 extends an extending column 36 to slide the back rest 16 along the stainless steel support tubes 32 to vary the distance of the back rest 16 from the seat 4 of the chair 2.

The feature of extending the back rest 16 is used in combination with the pivotal movement of the back rest 16 into a reclining position. As the back rest 16 reclines the linear drive 34 adjusts the extension of the back rest 16 so that the extension decreases in a predetermined ratio with the angular displacement of the back rest 16 as it reclines. When a patient is seated in the chair 2 with his or her back against the back rest 16, this coupled motion causes the back rest 16 to move to a reclined position without sliding over the surface of the patient's back. This improves comfort for the patient as sliding of the back rest 16 over their back may cause discomfort or injury to their skin.

Figure 7 also shows an articulated head rest 20 which is mounted on the back rest 16. The position of the head rest 20 is maintained using a head rest lock clutch mechanism 38. The articulated motion of the head rest 20 is shown in Figure 8. The head rest 20 is connected to the back rest 16 by a connecting member 40. A pivotal connection 42 between the head rest 20 and the connecting member 40 allows angular movement of the head rest 20 as indicated by arrows 44. Pivotal connection 46 between the back rest 16 and the connecting member 40 allows pivotal motion of the head rest 20 and connecting member 40 as indicated by arrow 48. Figure 9 shows a rear perspective view of the adjustable chair of the first embodiment. The chair 2 is provided with foot controls 50 for adjusting the chair 2. The foot controls 50 are removable from the base 6 so that they can be positioned in a suitable location where they can be easily accessed for adjusting the chair 2. Other controls for adjusting the chair 2 could be provided additionally or alternatively, e.g. hand-operated switches on the chair, or controls on a computer configured to communicate with the chair 2. The chair is provided with ball bearing castor pods 52 that are incorporated into the base 6. The castor pods are supplied with pressurised air by a pneumatic pump mounted on the base 6. Control of the pressure of supplied air provides suspension and ensures even loading on the castors. This allows the chair 2 to be moved within a surgery or between surgeries.

Figures 10-16 show a second embodiment of an adjustable treatment chair 102 in accordance with the present invention. Figure 10 shows a perspective view of the adjustable treatment chair, and Figure 11 shows a side view thereof. The adjustable treatment chair 102 of the second embodiment comprises a seat 104, a base 106, left 108 and right 110 arm rests, left 1 12 and right 114 support members (which also serve as height-adjusting means), an adjustable back rest 1 16, an adjustable foot and leg rest 1 18, and an articulated head rest 120. As in the first embodiment, the left 1 12 and right 114 support members are disposed directly beneath the left 108 and right 1 10 arm rests. The left 1 12 and right 114 support members comprise hydraulic rams for adjusting the height of the seat 104 and arm rests 108, 1 10.

In this embodiment, instead of a telescopic support member under the seat 104, there is a non-weight-bearing telescopic cover 122 underneath the seat 104. The cover 122 conceals a controller that effects the height adjustment of the seat 104 and arm rests 108, 110 via the hydraulic rams/support members 1 12, 114. The weight of the seat and of the patient on the seat is transmitted to the support members 112, 114 via a supportive collar on each of the support members 112, 1 14. This supportive collar is described below with reference to Figure 12. In the second embodiment, the arm rests 108, 1 10 have a different shape from the arm rests 8, 10 of the first embodiment. In both embodiments, the support members are disposed directly beneath the arms rests. As can be seen in the Figures, in both embodiments there is a portion of each arm rest (on which the patient can lean their weight when getting into or out of the chair) that is directly above the corresponding support member. One of the advantages of the present invention is thereby provided, which is that the patient can lean their weight on the arm rests, and their weight is directly transmitted to the ground by the support member underneath the arm rest. In addition to the portion directly above the support member, in both embodiments the arm rest extends forwards and/or backwards of said portion. This provides a surface for the patient to rest his/her arm on while seated. In the first embodiment, the arm rests 8, 10 extend forwardly and rearwardly of the support columns 12 to the same extent. This provides a large area for the patient to rest his/her arms while seated. In contrast, in the second embodiment, the arm rests 108, 110 extend predominantly forwardly of the support columns 1 12. This can provide improved ease of movement and increased comfort, for example, when the patient is lying in a fully reclined chair, as the patient may have more space to accommodate their upper body and more freedom of movement.

The foot and leg rest 1 18 of the second embodiment differs from that of the first embodiment. When the foot and leg rest 1 18 is fully lowered, as shown in Figure 1 1 , it is at an acute angle to the seat 104, rather than perpendicular, as is the case of the foot rest 18 of Figures 1 and 2. This provides improved comfort for the patient, who can sit with his or her knees bent at a more natural and more comfortable angle. The foot and leg rest 1 18 has a tapered shape, which allows clearance between the foot rest and castor pods 152 (described further below with reference to Figure 14) when the foot rest is lowered. In contrast, the foot rest 18 of the first embodiment has cut-out portions in the lower corners to allow clearance. The foot and leg rest 118 of the second embodiment is extendable. In contract with the first embodiment, the extension of the foot rest 18 is achieved using a mechanical linkage 124. Figure 12 shows a cross section of a schematic representing one of the arm rests 108 and the corresponding support member 1 12 (i.e. the hydraulic ram) of the second embodiment. The support member 112 comprises two portions: an inner portion 112a and an outer portion, or cover, 1 12b. The two portions 1 12a, 112b move together when the height of the hydraulic ram 112 is adjusted.

An annular supportive collar 154 is attached around the hydraulic ram 1 12. The seat 104 is provided with left and right apertures with diameters that correspond to the diameter of the hydraulic rams 1 12, 1 14, but which are smaller than the outer diameter of the collar 154. The seat 104 is positioned in use with the seat apertures located over the hydraulic rams 1 12, 114, such that the seat 104 rests on the supportive collars 154. The weight of the seat 104 and of the patient is thereby transmitted to the support members 1 12, 1 14, and then transmitted directly to the ground surface. It will be understood that the meaning of "directly to the ground surface" includes the possibility of the weight being transmitted via a base resting on the ground surface, as in the present embodiment.

Figure 13 shows the adjustable chair of the second embodiment in a reclined position, equivalent to the reclined position depicted in Figure 6. The hydraulic rams 1 12, 114 are retracted so that the chair 102 is in a lowered position, while the back rest 1 16 is reclined and the foot and leg rest 1 18 is elevated to provide a horizontal surface for the patient to lie on. As in the first embodiment, depending on the treatment or examination the patient is undergoing, a lowered reclining position may be more suitable than an elevated reclining position, or vice versa.

Figure 14 shows the back rest 116 of the adjustable chair 102 with the back cover removed so that the internal components are visible. The internal components correspond to those of the first embodiment, as shown in Figure 7, including stainless steel support tubes 132 and a linear drive 134 which extends an extending column 136 to slide the back rest 16 along the stainless steel support tubes. The linear drive 134 is positioned lower in this embodiment compared with the linear drive 34 of the first embodiment.

The adjustable chair of the second embodiment also comprises an articulated head rest 120, which has a different shape from the head rest 20 of the first embodiment. The head rest 120 has a curved shape that provides improved comfort for the patient in some cases, e.g. for particular uses of the chair or for patients of a particular stature. The position of the head rest 120 is maintained using a head rest lock clutch mechanism 138. The backrest 116 also has a different shape from the backrest 16 of Figure 7. Again, this alternative shape may provide increased patient comfort in certain circumstances.

Figure 15 shows a rear perspective view of the adjustable chair of the second embodiment. Similarly to the first embodiment, as shown in Figure 9, the chair 102 is provided with removable foot controls 150 for adjusting the chair 102, although the foot controls have a different configuration in the present embodiment. The chair is also provided with ball bearing castor pods 152 to allow the chair 102 to be moved within a surgery or between surgeries. Figure 16 shows a perspective view of the foot and leg rest 1 18 of the second embodiment with the foot and leg rest 1 18 in an elevated position. As explained above with reference to Figures 10 and 11 , the foot and leg rest 118 has a different shape from the foot rest 18 of the embodiment of Figure 1. Although the present invention has been described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the scope of the invention as set forth in the accompanying claims.