SLAC & SNAC Wrist
ScaphoLunate Advanced Collapse (SLAC) and Scaphoid Nonunion Advanced Collapse (SNAC) Wrist are both similar entities that describe a predictable progression of wrist arthritis due to a previous untreated Scapholunate ligament tear or a Scaphoid Nonunion (where the Scaphoid bone has fractured and not healed).
Unfortunately, this end stage problem is more common than we would like. This is partially attributable to the fact that both Scapho-Lunate ligament tears and Scaphoid fractures can often present with relatively minimal symptoms that are often dismissed by the patient as a "wrist sprain," and the fact the diagnosis is not uncommonly missed due to various factors such as being difficult to find on an Xray. For more information on these diagnoses, please refer to Scapho-Lunate ligament tears, and Scaphoid Fractures. Patients often cannot remember a distinct trauma that they had because it may have happened many years and even decades prior to final presentation of the SLAC/SNAC wrist.
Patients may experience pain on the top part of their wrist at rest, with range of motion, and especially when extending their wrist while weightbearing such as when simulating a push up. There may or may not be much swelling. Depending on the extent of the arthritis, there may also be significant limitation in the range of motion of the wrist as well.
Work-up usually first starts with an x-ray. However, further radiologic studies such as an MRI and/or a CAT Scan may be obtained to help further delineate the extent of the disease and to help dictate treatment options.
Dr. Lee will discuss various non-operative treatments based on the extent of the symptoms and functional impairment that the patient may have. The fact of the matter is that surgery is only indicated when the patient feels they have reached a tipping point beyond what they can take, and this is a very personal decision.
If opting for nonoperative treatment, patients will typically be treated with a removable thumb spica splint for up to 6 weeks. This can be removed for showering and washing the hands, but in general it is important to otherwise keep the splint on at all times, including sleeping. Corticosteroid injections and pain relieving medications such as Tylenol and NSAIDs (if not medically contraindicated) may have a role in temporarily helping to alleviate symptoms and can be discussed with Dr. Lee. Physical Therapy typically has a limited role in this disorder, but may also be prescribed depending on the severity of the disorder and the patient preferences.
If the symptoms and/or functional impairment becomes significant enough despite nonoperative treatment, the patient may request surgery. Again, this is a decision that the patient gets to make, not the doctor. If surgery is decided upon, there are a number of different surgical options that are available based on which joints in the wrist may be arthritic, which may be initially confusing to the patient. In general however, these surgeries fall into a category of "salvage surgeries." This means that they are meant to make you better than you are currently, but not necessarily back to normal.
There are many surgical treatments that have been described, but the probably the most commonly performed are called, Scaphoid Excision 4 Bone Fusion and Proximal Row Carpectomy, and Dr. Steven Lee has pioneered a new innovative technique called Proximal Row Carpectomy with Acellular Dermal Arthroplasty. A final last resort procedure is a Total Wrist Fusion.
Scaphoid Excision 4 Bone Fusion involves removing the Scaphoid bone and fusing the Capitate, Lunate, Hamate, and Triquetrum bones. It is a tried and true operation, one that can produce a relatively pain-free and durable wrist. However, the patient will need to be immobilized for at least 6 weeks and often is left with a wrist with decreased range of motion compared to the opposite side. It may however be best indicated for patients who engage in manual labor type activities where durability may be desired over range of motion, and don't mind being immobilized for a longer period of time.
Proximal Row Carpectomy involves removing three bones in the wrist (Scaphoid, Lunate, Triquetrum), and creating a more simplified wrist joint. It too is tried and true, but requires that the Capitate bone be relatively uninjured and preserved from arthritis. Immobilization with this averages 3-4 weeks and this procedure tends to produce an increased range of motion compared to the Scaphoid Excision and 4 Bone Fusion.
Dr. Steven Lee has developed the newest technique which involves doing a Proximal Row Carpectomy, but also introducing a Acellular Dermal Allograft between the bones to provide an extra "cushion" between the bones in order to provide more longevity and durability to the joint. It also does not require the Capitate to be pristine as in the standard Proximal Row Carpectomy. Finally, it was originally designed to replace a Total Wrist Fusion as most patients are not totally thrilled with the complete lack of mobility with a Total Wrist Fusion. Dr. Steven Lee has now been teaching this new technique to surgeons around the country. You can read about his innovative technique here.
Learn more about scheduling surgery.
Patients will be place in a wrist splint immediately following surgery. During the post-operative period, patients are encouraged to take 500 mg of Vitamin C daily, abstain from dieting, and to do everything possible to avoid additional trauma. We typically will encourage opening and closing of the fingers, but to refrain from any forced gripping, or lifting anything heavier than the weight of a coffee cup.
Depending on the procedure utilized, the patient will remain immobilized in a cast or splint for 3 to 6 weeks after surgery. Physical Therapy is usually started after the patient's cast is removed in order to regain back mobility and strength, and can last for at least 2 months. Patients will be encouraged to return to normal activities around 3 months after surgery. However, continued improvement from this difficult problem can continue for up to 1-2 years.
Learn more about post-operative care.
*It is important to note that all of the information above is not specific to anyone and is subject to change based on many different factors including but not limited to individual patient, diagnosis, and treatment specific variables. It is provided as an educational service and is not intended to serve as medical advice. Anyone seeking specific orthopedic advice or assistance should consult Dr. Steven Lee or an orthopedic specialist of your choice.
*Dr. Steven Lee is a board certified orthopedic surgeon and is double fellowship trained in the areas of Hand and Upper Extremity Surgery, and Sports Medicine. He has offices in New York City, Scarsdale, and Westbury Long Island.