Brief Description of the Images:

Fig. 1 -Trephining device with shield and pommel accessories

Fig. 2 - Trephining device without accessory attachments

Fig. 3-Close-up view of the burr as attached via the shank to the trephine handle illustrating 2the pointed tip of the vertex as well as the sharp flutes or racleurs

Fig. 4 - Obverse (Right-hand) side of hand restraint board with silhouette, pegs and parallel slots

Fig. 5 - Reverse (Left-hand) side of hand restraint board illustrating mirror image placement of silhouette, pegs and parallel slots with reference to the obverse side

Fig. 6 -Hand restraint board with asubject's hand restrained by wrist and finger straps

Fig. 7 - Manner of handling of trephine illustrated on a paper phantom

Fig. 8-Alternative handling of trephine with index finger used to apply additional pressure

Fig. 9-Alternative handling of trephine with cleft of the base of the palm used to apply additional pressure

References Cited:

Hugh, Donald C. Trephinator for Treating Subungual Hematomas. US 5,645,554

Herndon, Terry O. Drill Device and Method for Forming Microconduits. 2006/0041241; and US 2011/0040237 Kareil, Manuel Leon. Laser Apparatus for Making Holes and Etchings. US 5,947,956

Hagne, Leif. Burr. W01997011652A1

Kometas, Athas N. Self-Limiting Occlusion Reduction Burr and Method of Use. US 6,511,322 Bl

Justin, Daniel F.; et al. Curved Arthroscopic Burr.WO2013120004Al Golder, Joseph J. Restraint Device. US 5,335,957

Chapman, Angelina Maria; and Chapman, Daniel Thomas. Blood-Draw Finger Restraint. US 7,922679B1; US 2011/0120479A1; and US 7,972,28982

Mayorga, Oliver. Subungual Hematoma Drainage. Medscape.

http://emedicine.medscape.com/article/82926- overview#a09. Retrieved: 12 June 2014.

Boker, Andreas (2007). Can A New Nail Trephination Device Help Treat Nail Conditions? Retrieved: 22 August 2013.

Podiatry Today, 20(11). http://www.podiatrytoday.com/article/7900. Retrieved: 12 July 2013.

Patkin, M. (2001). A checklist for handle design. Ergonomics Australia On-Line, 15 (supplement), http://ergonomics.uq.edu.au/eaol/handle.pdf. Retrieved: 12 June 2014.

Robson, J.R.K. and El-Tahawi, H.D. Harness of Human Nail as an Index of Nutritional Status: A Preliminary Communincation. British Journal of Nutrition (1971), 26, 233.

Field of the Invention:

The invention generally relates to drilling devices especially those associated to surgical implements used in the treatment of finger or toenails. The invention also relates to devices that restrains the movement of the human hand as well as fingers.

Background and Prior Art: Crushing injuries to the extremities especially to the fingertips can result in an injury referred to as a subungual hematoma, a fairly common although under reported injury whereby blood collects under a toe or fingernail resulting in excruciating and exquisite pain relative to its size. Although the condition of and by itself is not serious, the resulting pain can be quite debilitating. The pain experienced from the injury is caused by resulting pressure from the accumulation of blood in the constricted space under the rigid structure of the toe or fingernail. The toes and fingers are, among other things, rich in nerve endings referred to as mechanoreceptors, i.e., sensory nerve endings that are sensitive to mechanical pressure or distortion. The intense pain resulting from the initial crushing injury damaging some of the interna! soft tissue matrix is then followed by the pain from the accumulating blood from the small ruptured blood vessels from which the leaking blood creates a third space unable to expand dorsaily because of the rigid nail structure and likewise ventraliy because of the underlying bone from the distal phalange of the afflicted finger. Thus the pressure generated by the trapped blood from the injured blood vessels is exerted onto these nerve endings resulting in the sensation of pain. The condition itself is usually self- limiting but depending on the patient and nature of the injury, the pain may be unbearable even if it is for a brief period of time. This intense pain has been known to drive some patients to extreme measures even to resorting to performing surgery on themselves in the absence of adequate medical attention.

This is a fairly common occurrence especially in industrial settings where one has to work with heavy objects in challenging work environments such as on busy factory floors, merchant marine vessels, remote mining operations as well as a frequent condition observed at emergency rooms, among others, injuries at industrial settings in remote locations often require patients to be evacuated to the nearest medical facility - often at great expense. When the pain is sufficiently severe, the patient will often seek out a clinician who will often choose to decompress the hematoma by breaching the integrity of the intact nail and thereby release the build-up of pressure via surgical nail avulsion, direct cautery or trephination. These procedures require knowledge, skills and tools that are unavailable at most remote industrial sites thus making evacuation of the patient a necessity.

Even though subungual hematomas are primarily classified as a condition to be treated on a first aid basis, currently available treatment modalities are difficult to apply since these steps are not very straight forward as they may require additional steps such as the possible need anesthetize a patient's finger; calibrate the depth of penetration of an instrument; or simply repurpose an existing "instrument" for the job at hand. These additional steps often make the course of treatment for subungual hematomas more challenging for novice first aiders who may opt to defer such treatments to more experienced healthcare workers - who may not necessarily be available at site. Moreover, even in well-equipped emergency rooms, clinics or just well -stocked first aid kits offer little if anything in the way of a simple, cost-effective, straight forward to use and specific treatment and/or device for subungual hematomas to say nothing of industrial work sites remote or otherwise.

Surgical nail avulsion requires the removal of the entire nail from the afflicted finger or toe under aseptic conditions and usually with anesthesia. It immediately relieves the pain from the pressure of the underlying hematoma but it also means more additional trauma for the patient who has to endure this procedure. It is quite painful, bloody and disfiguring as the patient will probably have to wait several weeks sporting crooked or disfigured nails before they starts growing properly again. Such a procedure is usually undertaken by a physician because of the level of knowledge and skill necessary to perform this procedure. As a considerable amount of pain is involved in this technique, anesthetic blocking of the digit will probably be required. Moreover, this procedure is usually more expensive to undertake compared to the other available treatments.

Nail trephination on the other hand is the other commonly performed procedure usually under professional medical supervision. One to several small holes may be directly drilled on top of the lesion on the affected nail. Usually an improvised drill such as disposable hypodermic needle with the tip sheared off is used for this purpose. At other times, a piece of wire (such as the end of a paperclip, also sometimes euphemistically referred to as the "paperclip method") is heated until it glows red hot and is applied to burn a hole onto the surface of the nail. In both instances, once the needle or piece of wire has breached the thickness of the nail there is a tendency for the instrument to traumaticaily stab into the underlying soft tissue because of the sudden "give" of the improvised instrument - adding to the patient's injury and discomfort.

Cauterization is the term applied to the practice or technique of using direct heat to remove or close off part of the body which, in the case of subungual hematomas, is exemplified by the "paperclip method". Techniques of this nature also have the dubious distinction of causing more psychological "pain" in the form of anxiety as the patient is forced to witness an improvised device as it actually burns through a part of his body and also anticipate the pain that is to follow.

Another cautery device in use is an electrically operated cautery device which makes use of a thin piece of electrically heated wire to burn a hole as in the "paperclip method". This cautery device usually consists of a simple circuit with a battery, a make-break switch and small piece of nichrome wire that are wired in series to a set of batteries and packaged in a pen-like housing for easy use. This design is meant to be disposable and, as it relies on heat to achieve its goal, it also tends to suffer from the same drawbacks of the "paperclip method", i.e., sudden penetration once the nail "gives". The patient may also sense the heat generated by the tip of the device which may add to his pain. For this reason, anesthetic blocking of the afflicted finger is also usually undertaken with this procedure.

Some patients reflexively jerk away from the trephine once the nail has been breached and are startled when blood suddenly squirts or oozes out of the aperture that has just been made. Fine drills, modified needles and improvised wire devices may be bent out of shape or even broken if and when the patient suddenly jerks his hand or foot away out of surprise especially when the patient has not been properly briefed on what to expect. It is also possible that such failures could result in accidentally lodging a foreign body in or around the targeted area from the device itself should it fail catastrophically or, perhaps, even result in accidental surgical avulsion.

A significant concern in all these procedures is how to control the depth of penetration of the instrument into the affected nail. The device developed by Donald C. Hugh in US Patent No. 5,645,554 incorporates a means of controlling depth or a "stopper" mechanism that halts further progress of its drill or blade beyond a set point and thereby preventing further penetration. It however fails to take into account the fact that human finger or toenails are usually only about 1 mm thick or, at most, usually no more than 2 mm. Devising a drill fine enough to breach the nail and equip it with a mechanical stopper for such a shallow depth would mean the operator of the device would have to maintain the drill bit at an almost perfectly perpendicular angle to the target while twisting and turning - and failing to do so would cause the stopper to engage prematurely thus rendering the device more difficult to use than expected. This difficulty would especially be more evident if several holes were needed in order to secure adequate surgical drainage. The mere presence of the stopper especially when fitted directly over the drill shaft itself would also tend to obstruct the direct line of sight of the operator when in use thus making it difficult for the operator to assess the progress of the drilling. In addition to this, the stopper mechanism would require some sort of manual calibration prior to use to insure that the drill is stopped precisely at the required depth and no further. It is still possible for a novice operator to overestimate the depth resulting in overshooting the nailbed. By the same token, it is also possible to underestimate the depth resulting in a false start. A degree of uncertainty therefore always attends the employment of this method.

A self-limiting burr invented by Athas N. Kometas with US Patent No. 6,511,322B1 for dental occlusal reduction uses a truncated conical shoulder configuration just above the actual cylindrical burr as a means of regulating a fixed depth removal of dental tissue. The cylindrical burr beneath the conical shoulder is designed to cut precise longitudinal grooves over and around the occlusal surfaces of teeth and thereby prepare the same for further dental restoration such as the placement of a dental restorative material and/or prosthetic. The truncated conical shoulder is not designed to cut into the dental tissue but rather act as a stopper or limiter to the further progress or penetration of the cylindrical burr tip which comes i fixed sizes. The action of this particular burr is to rout as much lateral dental tissue rather than axial penetration. Moreover, due to the variable thickness of human nail tissue and the difficulty of prior assessment of this thickness, the repurposing of this dental implement for decompressing subungual hematomas makes it susceptible to the same inadequacies and uncertainties of the preceding treatments modalities thus far discussed.

The patent of Leif Hagne's "Burr" with Patent No. W01997011652A1, on the other hand, specifically describes a truncated conical burr that is specifically designed to access dental abscesses that are in close proximity to adjoining teeth taking advantage of the cone's geometry. The acute angle of the truncated conical burr here is used primarily to remove as much dental material from the sides of the operative site thereby enlarging the hole thus created to facilitate debriding and subsequent dental restoration while at the same time minimizing the potential involvement of adjacent dental structures. However, the patent does not teach the inclusion of a sharp pointed tip with the burr. A sharp pointed tip for this burr is not necessary and may even be counterproductive for this application which may unintentionally damage underlying dental structures such as nerves. Another solution offered by Terry Herndonin, US Patent Publication Nos. 2006/0041241 and 2011/0040237, to achieve the creation of "microconduits" that could be useful in subungual hematomas and related afflictions of the nail uses an electronic circuit to automate the entire procedure of drilling and sensing the moment the nail has been breached and thereby relieving the operator of this burden. A small electric motor with an appropriately sized drill and support mounting is controlled by an electronic circuit that is designed to sense changes in electrical impedance through the body of the patient subjected to this procedure. A small electrode is attached to the body of the patient while the motorized drill is in operation. Once the drill breaches the nail thickness and comes into contact with the underlying subcutaneous tissue the drill bit, which is also connected to the electronic circuit and thereby forming the second lead for the sensing circuit for impedance, causes the circuit to close and thereby signals the electric motor to stop and/or withdraw.

US Patent No. 5,947,956 referred to as the Onycholaser™ by Manuel Leon Karell on the other hand teaches the use of short laser pulses of high peak power to induce nail trephination and is also able to etch decorative designs on the nail surface for aesthetic reasons. The short bursts of energy from the laser can be calculated to burn a hole through the nail but only just enough to facilitate drainage or access to the afflicted nail. The sheer technical complexity of this device that undoubtedly will require some technical expertise relative to the simplistic nature of the injury in question again argues against its serious consideration as a treatment modality for this condition or at least to any large scale application and is therefore very unlikely to be used as a treatment at remote industrial sites. This design is complicated, expensive and requires specialized training to operate thereby making this design unsuitable for industrial work sites and other potential areas where emergent conditions are to be expected, especially where costs and accessibility are considerations. Lastly, the patent of Daniel Justin, et al. with Patent No. WO20131200O4A1 entitled

"Curved Arthroscopic Burr" is a complex powered surgical instrument used to resect a considerable amount of tissue relatively tangential to the longitudinal axis of said instrument. Multiple ganged burrs resembling spurs are operated in unison and serially in such fashion as to abrade and thereby sculpt the targeted tissue. Although this device also engages the use of burrs to resect tissue, its design, overall complexity, method of use and intended application all but preclude it from being considered as a device for the treatment of afflictions of the human nail.

Nail trephination treatment techniques may necessitate the further use of a means of restraint to render the finger and/or hand immobile in the course of the treatment. Angelina Maria and David Thomas Chapman in their blood draw finger restraint device with US Patent Nos. 7,922679B1; 2011/0120479A1; and 7,972,28962 teach of a small finger- applied device designed to extend and straighten out individual fingers to make it accessible to medical personnel for blood extraction which makes this invention ideal for use in very young children who instinctively make a fist at the prospect of this medical procedure. This device makes use usually of a pliable piece of plastic material that is wound around the distal interphalangeal joint of a targeted finger in such a configuration and manner as to induce straightening and restrain the joint thereof. This device does not seek to restrain multiple fingers and the entire hand simultaneously. Moreover, although it is possible to use several of these devices to restrain several individual fingers simultaneously, it still does not diminish the possibility of sudden jerking movements of the hand if the patient is startled. Lastly, since the fingers are not secured on a larger separate hard surface, it makes it more difficult for medical personnel to position said finger(s) on tables or other similar surfaces to facilitate working on the same.

It is the object of the present invention to introduce a nail trephining device with an accompanying hand-restraint assembly that avoids all the known inadequacies of the aforesaid treatment methods and instruments and which can easily be deployed and utilized even in remote areas where adequate medical care is not readily available

Detailed Description of the Invention: The invention is composed of a set with a handheld nail drilling device known as a trephine (Fig. 1) that utilizes a sharp pointed conical burr (3) that enables the operator to penetrate and make small circumscribed holes on a human finger or toenail to decompress the buildup of fluids resulting from previous blunt trauma as well as a hand restraint board (Fig. 4 and 5) to secure the hand to be operated on for the duration of the surgical procedure. The attachment to the trephine which enables it to create small circumscribed holes on the surface of the human nail is an acutely sharp pointed conical burr (3) that allows for the quick removal of nail tissue and yet controlled penetration of the nail itself. The hand restraint board (Fig. 4) is a rigid flat hard surface unto which a silhouette (11) of the human hand is imprinted as well as pegs (12a -12d) have been mounted through perpendicular to its flat surface so as to guide the placement of and aid in the immobilization of the hand of the patient. The strategic placement of straps (16a-16e, 17) on the hand restraint board through slotted holes located across the outstretched fingers (13) and wrist (14) effectively secures the patient's hand onto the board's flat surface (15) and thereby minimizing the risk of inadvertent movement thereof. A mirror image of the silhouette as well as the placement of the pegs and straps is provided for on the reverse side of the hand restraint board (Fig.5) in such a way as to allow the opposite hand of the patient to be so restrained as needed. The trephining device (Fig.1) is a self-depth-regulating surgical drilling implement that is able to breach the integrity of finger and toenails so as to bring about the decompression of subungual hematomas. It has a pencil-like appearance (Fig. 2) with a cylindrical body (la) also referred to as the handle to which a pointed acutely conical burr (3 and 4), hereinafter referred to simply as the "burr", is attached by means of a thin shank (5) and centered at one end of the cylinder (la) along its longitudinal axis where the handle is slightly chamfered (8) or rounded at this end. The attachment of the burr to the handle via the shaft is fixed in such a way as to insure that any rotational and/or compressive force generated at the handle by the operator is effectively transmitted to the burr especially at its tip or vertex (4). The trephine handle itself (la) may be rendered in metal (stainless steel, aluminum, etc.), plastic, wood or some other suitable material. The preferred embodiments of the burr (3) is in metal or other durable material such as ceramic, engineering plastic or any other suitable material that is capable of delivering its cutting and/or abrasive qualities to remove small quantities of nail tissue and thereby create small circumscribed holes or apertures on the surface of the nail to bring about the decompression of trapped hematomas underneath while at the same time ensuring the slow axial penetration of the vertex (4).

The burr (3) has a conical shape ending in a sharp point (4) and fluted with sharp ridges and furrows (3a) radiating all around its base to its pointed end so as to act as both a drill and a scraper. The cone-like geometry of the burr (3) serves as a drilling tool by virtue of the cutting and/or abrasive action of the burr and a natural check to the progress of depth penetration by virtue of the ever expanding diameter of the conical base relative to its longitudinal travel as it traverses the nail thickness making it extremely unlikely to suddenly stab into the underlying nailbed given the natural hardness and the minimal thickness of the hitherto normal human nail. A sharp tipped conical burr (3 and 4) is thereby a de facto delay mechanism and, given that the burr is able to cut into material from side to side (3a) as well as at the tip (4) , the instrument is thereby tolerant to minor deviations and oscillations in the positioning and operation of the instrument in the course of drilling through the nail that is commonly expected in the use of similar hand tools. Another preferred embodiment of the trephine is a sharp pointed conical tip with a sufficiently abrasive surface such as, but not limited to, industrial diamonds in lieu of sharp flutes. The penetration and removal of nail tissue in this case is achieved by attrition.

The trephine also has a knurled surface (2) proximal to the chamfered (8) end of the handle whereupon the burr is attached. The knurling allows the operator to firmly grasp, control and otherwise manipulate the device without slippage. A slightly recessed narrow rim (6) is located a short distance from the insertion of the burr within the knurled area of the handle. The rim allows for the insertion of a circular piece of thin flexible transparent plastic sheet referred to as the shield (7) that bears a circular hole at its center which allows it to articulate with and be held in place by the rim when thus engaged. The shield (7) may be inserted by the operator through the handle to protect him from any debris that may be forcefully discharged from the nail once it is breached, otherwise the shield may be removed to facilitate storage of the device set when not in use. The transparent shield (7) allows the operator to visibly monitor the progress of the procedure without fear of being contaminated in case of an inadvertent discharge. The trephine is intended to be held in a manner similar to holding a pen (Fig. 7) whereby the operator holds and rotates it using the first three digits, i.e., the thumb, index and middle fingers close to the working (distal) end of the device and close to the proximal end of the device resting on the distal cleft of the index finger upon flexion; allowing the vertex (4) of the conical burr (3) to be perpendicular to the work surface. As the instrument is primarily grasped and manipulated using the first 3 digits of the hand, the part of the handle where this takes place is knurled (2) to facilitate control and ease of use. The knurled surface allows the trephine to be grasped firmly and facilitate easy rotation of the instrument back and forth to engage the drilling action of the burr.

The pommel (10) may come in various embodiments such as but not limited to a rounded ball, a flattened circular disk or some other suitable configuration. In this modality, the trephine may be gripped by the first, third and fourth digits by the knurled surface (2) (thumb, middle and ring fingers) with the tip of the second digit (index finger) placed just above the pommel (10) and thereby put additional pressure to bear on the trephine thereto. Alternatively (Fig. 9), the trephine may also be gripped by the operator at the knurled surface (2) using tips of the first three digits (thumb, index and middle fingers) to manipulate the trephine while the butt (9) or pommel (10) rests in between the cleft of the thenar and hypothenar eminences of the palm of the hand applying additional pressure to the instrument thereby.

The hand restraint board (Fig. 4) is composed of a thin rigid lightweight flat board of material such as metal, plastic, wood, paper or composite thereof upon which the silhouette (11) of a human hand with fingers spread apart is printed on the obverse side and a mirror image of the same silhouette (11) on the reverse side. The silhouette (11) non-verbally facilitates the placement and the strapping in of the patient's afflicted hand in a position that will facilitate the procedure. Three rounded pegs (12b-12d) mounted securely and rise above the surface of the board correspond directly to the positions of the webs between the second to the fifth digits (index to the pinky) of the hand and thereby comfortably position it palm-faced down on the board. A fourth peg (12a) is located pressed against the medial aspect of the proximal phalange of the first digit (thumb) thereby causing it to be drawn away from the rest of the fingers on the board's surface. The pegs (12a-12d) and the silhouette (11) also correspond to their same relative positions on the reverse side of the board (Fig. 5) thereby mirroring it and therefore effectively capable of positioning the opposite hand if need be. This mirrored configuration allows for a single board to handle either or both hands (sequentially) rather than having separate boards to service either hand separately. Moreover, the entire board itself makes it much easier for the operator to position the subject's hand that is restrained on the board on a table or similar affordance so as to facilitate work thereon.

The hand restraint board (15) is also afforded two parallel slotted openings (13) for each of the five digits of which a thin strap (16a 16e) of natural or synthetic material is threaded through. These parallel slots are located at the level of the middle (interphalangeal) joints for each of the five digits on the silhouette. Parallel slotted openings are likewise provided at the level of the wrist (14) along with a suitably longer strap (17) to secure the entire hand at this level of the silhouette. The straps are provided with a means of being adjusted and fastened to create a loop and accommodate various hand and finger sizes and thus restrain the appendage in question. Fasteners may consist of, but not limited to; fabric hook and loop fastener, a buckle-type fastener, or some other configuration thereof capable of securing and adjusting these looped straps as such. When these straps are thus engaged and used in combination with the pegs, the straps effectively arrest either hand palm-faced-down onto the hand restraint board (Fig. 6). The hand restraint board effectively prevents the flexion of the fingers and/or wrist of either hand of the patient or subject to prevent reflexive or otherwise spontaneous jerking movements thereof.