ABSTRACT: The patient suffering from limb deformities requires palliative and supportive care postoperatively as well as assistance regaining mobility. The veterinary nurse's primary role is to provide this care, and the use of pain assessment scales upon recovery are a critical tool in aiding return to normal function.

Physiology

The radius and ulna are collectively known as the antebrachium. The ulna is the thinner of the two bones, whilst the radius has significant contact with the carpus and is also the load-bearing bone of the lower forelimb.1

A deformity of these two bones can cause a multitude of problems; namely gait abnormalities, muscle atrophy and disproportionate muscle build-up. One cause of deformity is early closure of the distal ulna growth plate as this impedes the growth of the radius, thus causing the radius to bow.2

The forelimb of patients with this condition resembles that in Figure 1.

Figure 1: Deformity resulting from early closure of the distal ulna growth plate

Here it is clear the radius is bowing and the ulna is short. Diagnostic radiographs of the antibrachium include the elbow and carpal joints to assess deviation.3 The limb of the patient in Figure 1 had a carpal deviation of 90 degrees.

Pre-operative considerations

The radial and ulna osteotomy involves the removal of a wedge of bone that is measured pre-operatively by the surgeon. The subsequent deficit is then reduced with the application of a plate and the repair is straightened with a pin, which creates a lengthening of the ulna.

Following premedication with an opioid, such as buprenorphine, and a sedative, for example, acepromazine, induction of anaesthesia is carried out using propofol and maintained with isoflurane. Once stable, the patient is placed in lateral recumbency ready for the limb to be clipped for surgery.

The distal carpus around the whole circumference of the limb and up to mid-scapula is clipped and a bandage is applied to the foot, with a loop left ready for the limb to be attached to a drip stand or similar apparatus, in order to maintain it in a suspended position. The patient is moved into the theatre and the limb is then prepared aseptically for surgery.

Peri-operative procedure

The limb is prepared for surgery using the ‘four quarter’ draping technique, ensuring that the lateral surface of the ulna is accessible.'1 The ‘four quarter’ draping technique requires the surgeon to place four drapes around the limb, beginning with the surface closest to them. This allows them to apply a sterile bandage around the preliminary bandage on the foot and then place the limb down onto the drapes.

Required instrumentation will include plate benders, screws, drills, depth gauges, pins and pin cutters. A battery or air-driven bone saw will also be required, and the scrub nurse or surgical assistant will be required to provide cold fluid irrigation whilst the radius and ulna are being resected. This can be achieved by means of a wide gauge needle or via a pressure bag.

All instruments and equipment should be arranged on the instrument trolley by the scrub nurse during the pre-operative period, but it is always useful to have access to spares and know the surgeon’s ‘Plan B’ if the original procedure does not go to plan.

Postoperative measures

Lateral and caudal/cranial radiographs are taken to ensure that the partial carpal arthrodesis plate is situated correctly, and that the screws are not over long and interfering with the ulna (Figures 2 & 3) A pin is placed to maintain alignment, whilst allowing the ulna to move into the correct position and to increase the strength of the repair.

Figures 2 and 3: Lateral and caudal/cranial radiographs are taken to ensure that the partial carpal arthrodesis plate is positioned correctly

In the immediate postoperative period, the patient is placed in lateral recumbency with the affected limb uppermost on a well-supported bed to provide comfort. As this is a prolonged procedure, the patient may become hypothermic and, therefore, close monitoring of the patients temperature is important.

A bandage is applied for a period of 12 hours postoperatively to reduce swelling. Ensuring that the bandage does not become soiled or chewed is important, so a ‘Buster’ collar should be placed on the patient once it has regained full consciousness. Opportunities for supported urination outside are also important. Water bowls should be heavy to avoid their being tipped over easily.

Following removal of the bandage, cold packs may be applied to the limb to ensure that swelling does not occur. They need to be wrapped in a towel to avoid cold burns and must not be placed directly over the plate as this will absorb the cold much faster than the surrounding tissues and remain cold for a much longer period, possibly devitalising surrounding soft tissue.

The nurse should monitor for signs of pain; which may include vocalising, tachycardia, tachypnoea and hypersensitivity. Multi-modal analgesic therapy will be required to prevent pain. This may include opioids, non-steroidal anti-inflammatory drug (NSAIDS) and possibly use of constant-rate infusions of compounds such as ketamine.

It is important to maintain the normal range of motion of the joints, both proximal and distal to the repair. As bone healing increases, more aggressive activities such as hydrotherapy and weight-bearing exercises may begin.5 This is decided by studying postoperative radiographs, which are normally taken four weeks after surgery.

Figure 4 demonstrates the outcome of such surgery: the right limb appears less bowed, although the paw still has rotation from the deformity which has occurred owing to the angle at which the radius had grown.

 Figure 4: T
he outcome of corrective surgery

The control of swelling and minimising the loss of joint and muscle function allows the patients limb to return to as normal a range of function as possible.

Supporting the patient by the use of slings when it initially begins to ambulate helps to prevents loss of balance and proprioception.

Physiotherapy can aid in preventing any gait and posture abnormalities that could impede rehabilitation as the patient may compensate by using the other limb and might continue to do so after rehabilitation. Physiotherapy should be undertaken under the guidance of a qualified veterinary physiotherapist and the veterinary nurse can work alongside this individual to ensure the patient returns to optimal function.

Conclusion

The ulna and radial osteotomy patient requires dedicated nursing care throughout its hospitalisation. Owners will also require guidance with respect to care, including basic physiotherapy techniques which can be continued at home under the veterinary surgeons direction. Regular visits to the practice to see a chartered veterinary physiotherapist and the veterinary nurse, together with the length and the nature of the recovery period, enable the veterinary nurse to build a firm bond with both patient and client, which can be very fulfilling. 

Author

Laura Daniels RVN MBVNA

Laura has been in practice for five-and-a-half years, working in a busy Tier-3 hospital based in Cheshire. Since qualifying in January 2009, she has developed a keen interest in orthopaedic nursing care and is working to build her knowledge and experience in this field.

To cite this article use either

DOI: 10.1111/j.2045-0648.2012.00150.x or Veterinary Nursing Journal Vol 27 pp 98-100

References

1.   RIEGGER-KRUGH. C.. MILLIS, D. and WEIGEL. J. (2004) Canine Anatomy In: Millis. D.. Levine. D. and Taylor. R. Canine Rehabilitation and Physical Therapy, Saunders. Missouri. p40

2.   DENNY, H. and BUTTERWORTH. S. (2001) Early Closure of The Distal Ulnar Growth Plate In: Denny, H. and Butterworth, S. A Guide To Canine and Feline Orthopaedic Surgery 4th Ed.. Blackwell Publishing. Oxford. p398

3.   LANGLEY-HOBBS, S. (2006) Disturbances of Growth and Bone Development In: Houlton, J.. Cook, J., Innes. J. and Langley-Hobbs. S. BSAVA Manual of Canine and Feline Musculoskeletal Disorders. BSAVA Gloucester. p51.

4.   PIERMATTEI. D. and JOHNSON. K. [2004] Approach to the Distal Shaft and Styloid Process of The Ulna In: Piermattei, D. & Johnson. K. An Atlas of Surgical Approaches to the Bones and Joints of the Dog and Cat 4th Ed.. Saunders, Pennsylvania. p240,

5.   LEVINE, D.. TAYLOR. R., and MILLIS, D. [2004] Common Orthopaedic Conditions and their Physical Rehabilitation In: Millis. D., Levine. D.. and Taylor, R. Canine Rehabilitation and Physical Therapy. Saunders, Missouri. p364.

• VOL 27 • March 2012 • Veterinary Nursing Journal