Keller’s arthroplasty is a well-established surgical procedure used to treat hallux valgus (a deformity of the big toe) and hallux rigidus (a form of arthritis in the big toe joint). This procedure, named after Captain William Keller, who first reported it in the early 20th century, continues to be a prominent method for addressing painful conditions affecting the first metatarsophalangeal (MTP) joint.
Understanding Hallux Valgus and Hallux Rigidus
Hallux valgus is characterized by the abnormal angling of the big toe toward the second toe, which often results in a bunion. This condition is painful and can lead to difficulty walking and wearing shoes. Hallux rigidus, on the other hand, is a degenerative arthritis condition that limits the movement of the big toe, leading to stiffness and pain.
While various treatments exist for hallux valgus, including osteotomies and bunion surgery, hallux rigidus is typically treated with MTP joint fusion to alleviate pain. However, patients presenting with both hallux valgus and hallux rigidus pose a more challenging scenario. In these cases, surgery must both address the deformity and preserve joint movement.
The Keller Arthroplasty Procedure
Keller’s approach is a resection of the proximal part of the first toe’s proximal phalanx, along with the excision of the medial eminence of the first metatarsal. The primary goal is to alleviate pain while preserving as much function of the toe as possible, especially in older patients or those who are less physically demanding.
The surgery involves a straightforward technique using a dorsal medial incision, followed by careful dissection to remove the necessary portions of bone and soft tissue. The procedure requires no extensive joint fusion, which helps maintain some level of motion in the toe. Following the surgery, patients are typically immobilized in a special shoe for several weeks, after which they gradually begin weight-bearing and range of motion exercises.
Outcomes and Effectiveness of Keller’s Arthroplasty
The outcomes of Keller’s arthroplasty have been reviewed in multiple studies, revealing a high rate of satisfaction among patients. Pain relief is one of the most significant benefits, with a substantial number of patients reporting improvement in their ability to wear regular footwear and participate in daily activities. However, the success of this surgery can vary depending on patient age, the extent of the deformity, and whether hallux valgus and hallux rigidus are both present.
In one study, approximately 39% of patients reported excellent results, and 37% reported good results. Radiological assessments showed a significant reduction in the hallux valgus angle, which aligns with the surgical goal of correcting the deformity. However, one notable complication that arises in some cases is metatarsalgia, or pain under the ball of the foot, which can occur due to the altered mechanics of the foot following surgery. In some cases, the toe may also become “cocked up,” leading to difficulties in shoe fitting.
Comparison with Other Surgical Options
Although Keller’s arthroplasty has its drawbacks, particularly the potential for post-operative complications, it compares favorably with other treatment options such as first MTP joint fusion. The fusion procedure, while effective in alleviating pain, leads to the permanent loss of movement in the big toe, which can severely affect walking and overall foot function. Keller’s arthroplasty, in contrast, preserves some degree of motion, making it a preferable option for older, less active patients who prioritize pain relief and functional ability over a complete restoration of the joint.
In some studies, the satisfaction rates for Keller’s arthroplasty have been comparable to those for joint fusion, with approximately 87% of patients reporting good to excellent outcomes​.
The Importance of Age and Patient Expectations
Age plays a crucial role in the outcomes of Keller’s procedure. Younger patients, especially those under 60, may experience a higher incidence of complications such as metatarsalgia or reduced function, and might be better suited to more invasive procedures like joint fusion. Conversely, older patients tend to do well with Keller’s procedure, as they are often less concerned with the loss of movement and more focused on alleviating pain and improving quality of life.
Moreover, cosmetic outcomes also play a significant role in patient satisfaction. Many patients, particularly women, report dissatisfaction with the appearance of their foot post-operatively, especially if the hallux becomes noticeably shorter than the second toe. This cosmetic concern can be a key factor influencing the decision to undergo Keller’s procedure.
Conclusion
Keller’s arthroplasty remains a valuable option for the treatment of adult hallux valgus associated with hallux rigidus. It is especially beneficial for older, less active individuals who prioritize pain relief and the ability to wear regular shoes. While the procedure offers several advantages, including a relatively simple technique and preservation of joint movement, it is not without complications. Careful patient selection, proper surgical technique, and realistic expectations regarding the functional and cosmetic outcomes are critical to achieving the best results.
For more complex cases or younger patients with higher functional demands, alternative treatments such as joint fusion or implant arthroplasty may be more appropriate. However, Keller’s procedure continues to be a reliable and effective solution for a specific group of patients suffering from these painful and debilitating conditions.
