Lapidus Arthrodesis is a surgical procedure primarily used to treat hallux valgus (HV) deformities, especially when other methods have not been effective. The procedure involves the fusion of the first tarsometatarsal (TMT-I) joint, which connects the first metatarsal bone to the medial cuneiform bone in the foot. This operation is particularly effective in addressing moderate to severe cases of hallux valgus, a condition where the big toe deviates inward, causing discomfort and misalignment.
What is Lapidus Arthrodesis?
Lapidus Arthrodesis is often recommended when there is hypermobility (excessive movement) at the TMT-I joint, which contributes to the instability of the first metatarsal. This hypermobility can lead to misalignment, causing problems like bunions, pain in the big toe, and difficulty walking. In such cases, a fusion of the joint is performed to stabilize it, thereby reducing pain and correcting the deformity.
History of Lapidus Arthrodesis
The technique was first described by Dr. Paul Lapidus in 1934 as a way to address hallux valgus deformities with a metatarsal-phalangeal joint. Over time, the method evolved, and in 1979, Hansen reintroduced the procedure, refining it for better results. Modern variations of the procedure continue to be employed today, with modifications that improve outcomes, such as better fixation techniques and reduced complication rates.
Indications for Lapidus Arthrodesis
Lapidus Arthrodesis is typically recommended for patients with moderate to severe hallux valgus deformities. These deformities are diagnosed based on the angle between the first and second metatarsals (intermetatarsal angle, IMA) and the angle of the big toe (hallux valgus angle, HVA). If the IMA exceeds 16–20° and the HVA exceeds 31–40°, the patient is considered for this procedure. In more severe cases, these angles can exceed 40° and 20°, respectively. Additionally, it is considered for patients who have failed other non-surgical treatments, such as bracing or padding.
Preoperative Diagnosis
Before performing the procedure, a thorough evaluation of the patient’s condition is necessary. This includes a detailed medical history, physical examination, and imaging studies. Radiographs (X-rays) of the foot are essential to measure the IMA and HVA angles. Sometimes, advanced imaging techniques such as MRI or CT scans may be used to assess any underlying joint degeneration. The Beighton Score, which helps determine the general hypermobility of the patient, is also useful in selecting appropriate candidates for the procedure.
Surgical Technique
The procedure is typically performed under general anesthesia, with the patient in a supine position. A pneumatic tourniquet is used to minimize blood flow to the area. The surgeon makes small incisions on the medial side of the foot, allowing access to the TMT-I joint. Arthroscopy, a minimally invasive technique, is often employed to reduce the amount of tissue and bone removal necessary. The joint surfaces are prepared for fusion by removing the articular cartilage and performing microfracture of the underlying bone. Once the surfaces are ready, the first metatarsal is positioned in the correct alignment and stabilized using screws or plates.
In some cases, additional procedures may be necessary to correct other deformities or to stabilize the joint further. These might include a medial release of the soft tissues or repositioning of the sesamoids, small bones that assist in the movement of the big toe. Once the fusion site is prepared and stabilized, the joint is left to heal.
Postoperative Care
After surgery, the patient will typically be required to wear a cast or a walking boot to protect the foot and ensure proper healing. Non-weight-bearing is usually required for several weeks to prevent stress on the healing bones. Radiographs are performed to ensure that the joint is fusing correctly. In most cases, patients can begin partial weight-bearing after 6–8 weeks, with full weight-bearing permitted after approximately 12 weeks.
Physical therapy is also an important part of recovery. It helps restore mobility to the foot and ankle, improve strength, and reduce swelling. In some cases, patients may experience prolonged swelling or discomfort, which can be managed with appropriate medication and rest.
Results and Complications
The results of Lapidus Arthrodesis are generally good, with most patients experiencing significant relief from pain and improvement in foot function. However, like all surgical procedures, there are potential risks and complications. One of the most common complications is nonunion, where the bones do not fuse properly. This can occur in up to 10% of cases, although advancements in surgical techniques have reduced the incidence.
Other potential complications include:
- Transfer metatarsalgia (pain in the other metatarsals)
- Recurrence of hallux valgus
- Injury to surrounding soft tissues
- Hardware-related complications, such as irritation or loosening of screws
- Long-Term Outcomes
The long-term success of the procedure depends on several factors, including the patient’s overall health, adherence to postoperative instructions, and the presence of any additional foot deformities. Studies show that the results of Lapidus Arthrodesis remain stable for many years, with a low rate of recurrence of hallux valgus or complications after the first year of recovery.
Patients who undergo the procedure often report high levels of satisfaction, especially those who had significant pain or difficulty walking before surgery. Many are able to return to daily activities, and some even regain their ability to participate in sports, although this may take longer for athletes.
Conclusion
Lapidus Arthrodesis is a highly effective surgical option for treating hallux valgus, particularly in cases of moderate to severe deformity or joint instability. While the procedure has a long history and a proven track record, advancements in surgical techniques and postoperative care have made it even more reliable and minimally invasive. Patients who are suitable candidates for this procedure can expect to experience significant relief from pain and improved foot function, allowing them to return to normal activities with reduced discomfort.
