I was assisting a surgeon today when I discovered a phenomenon that is important to identify- the humble avocado has been generating
hand injuries across the globe! A quick internet search revealed it was true. Last year a paper came out in the Irish Medical Journal describing a 32 year old woman who sustained an avocado related injury requiring surgery. This article was followed up by a letter to the editor in the Journal of Hand Surgery European Volume reporting on 18 patients with similar avocado associated injuries. I thought this public health issue was so important it had to be followed up on!
First of all I have nothing against avocados per se. Avocados contain magnesium, fibre and potassium which are all good and contribute to improved cardiovascular health – increased fibre means lower risk of cardiovascular disease, potassium has been shown to have some impact on blood pressure and magnesium taken in a normal diet is associated with reduced ischaemic heart disease. Intake has also shown an increase in serum HDL, which is important in calculating and improving a patient’s absolute cardiovascular risk.
The interesting part of this tale is it appears to have been identified by the press first and then picked up in medical journals. These injuries are usually reported as a penetration of the non dominant hand with a single wound as a result of a failed attempt at avocado seed removal…..we’ve all been there. Most of these stab wounds were around the base of the index and middle fingers in the palm. Some injuries were bad enough that they went through the hand and most involved laceration of nerves or arteries in the hand or finger. The mechanism of injury is described as the person having pushed the knife tip into the avocado seed, with subsequent sliding off the seed into the hand. There have even been calls for warning labels to be stuck on these fruit.
The biggest concern with any hand laceration is the risk of injury to blood vessels and nerves in the hand and fingers particularly as many of these important structures run very close to the skin. Every finger has a digital nerve running along both sides. This nerve is about 3mm in diameter and its path is also accompanied by an artery and a vein close by – this is called the “neurovascular bundle”. You can imagine where your neurovascular bundle runs by looking at the side of your finger with all joints flexed. The vessels and nerve run along the ends of the creases, as shown in the picture. Luckily these nerves only supply sensation to the finger and its injury does not normally affect movement or strength in the finger. By the time the nerve reaches the finger tip it divides into a web of terminal branches and these branches are too small to repair if lacerated meaning that sensation can be permanently damaged if the nerve is cut.
Nerves can often be repaired surgically however need to be repaired under magnification where careful reconnection of the lacerated nerve ends takes place by bringing together the outer membrane by a skilled surgeon. This is a very fine procedure, and despite repair the patient can sometimes be left with permanent numbness! Splinting of the finger is required after repair as it is important that the nerves remain tension free during the healing process, this typically takes up to 6 weeks. As I mentioned the nerve also travels with blood vessels so a nerve laceration is often accompanied by an artery or venous injury as well. These vessels can also be repaired, most of the time, however its important to note any blood or nerve injury is always considered a medical emergency. If you’re worried you may have lacerated your neurovascular bundle you must seek medical attention immediately.
So are avocados really causing increased problems with numbness in fingers and loss of blood to finger tips? If so then they need to be dealt with.
The final twist in this tale is found at the very end of the letter to the editor mentioned at the beginning of this post. The researchers of this study revealed their statistics were from a 24hr emergency hand injury clinic servicing a population of 1.2 million, so roughly double the population of the Gold Coast. They had gone back over 7 years worth of patient presentations and identified only 18 patients over this entire time who had presented with avocado related injuries. In their opinion there was no specific injury pattern that separated ‘Avocado Hand’ from other stabbing hand injuries. They concluded that the term in fact was redundant indicating that avocados are not the dangerous fruit that they have been made out to be.
So not everything you read on the internet is true. But you should still be careful when removing the seed of an avocado.