Of course the old adage that common things occur commonly holds true, with most weeks through the summer sprinkled with a fair number of itching dogs and similarly coughing dogs through the winter.

However, other less common conditions frequently come in runs after months of not being seen.

More usually an ever present fixture at Wooler, Steve happened to drop into our Morpeth surgery a few weeks ago, primarily to see at first hand some of the new equipment that the merged practice has allowed us to invest in.

Impressed by the digital X-ray developer that enables us to get much more information from conventional radiographs, we started chatting about orthopaedic cases.

Steve had recently operated on a working dog to repair its ruptured cruciate ligament, a procedure I hadn't performed for probably six months, an unusually long period. Sod's law, in the fortnight since I have done four!

The cranial cruciate ligament is a structure that is integral to the stability of the stifle joint (the equivalent of our knee), allowing the joint to smoothly flex and extend but ensuring that the articular surfaces don't grind against each other.

The injury is actually fairly common in dogs because of their athletic nature, a problem shared with footballers; with both Michael Owen and Gazza suffering ruptured cruciates in their careers.

There are a multitude of different techniques of varying complexities to correct the problem; the most recent of these involving precise cuts made to the tibia (or shin bone) to form a step in the joint that prevents the painful and damaging grinding action. This surgery is very specialised and confined to referral centres.

Another widely used technique and one that I have become particularly familiar with in the last few days is to take a strip of muscle carefully dissected from the quadriceps (the thigh) and then gently passed through the joint as a natural replacement for the ruptured ligament.

In larger breeds this graft can be reinforced with a nylon wire to provide extra strength and give the strip of muscle a chance to establish a good blood supply.

Recovery from the surgery generally takes about six to eight weeks (a good deal quicker than the footballers mentioned) with a fair chance of a complete return to athletic function.

Unfortunately, the number of miles that the average canine stifle travels in its lifetime results in an inevitable degree of wear and tear and any disruption to the precise mechanics of the joint will ultimately predispose it to arthritis.

Whichever method is used to stabilise the joint, the damage caused by the initial injury sows the seeds of the arthritic process and consequently these cases require careful weight management and exercise control post operatively to minimise any deleterious changes.

Like buses, I'll probably not see another cruciate case for six months, but that's what makes vetting so interesting.